System for treating embolism and associated devices and methods

ABSTRACT

Systems and methods for the intravascular treatment of clot material within a blood vessel of a human patient are disclosed herein. A method in accordance with embodiments of the present technology can include, for example, positioning a distal portion of a catheter proximate to the clot material within the blood vessel. The method can further include coupling a pressure source to the catheter via a tubing subsystem including a valve or other fluid control device and, while the valve is closed, activating the pressure source to charge a vacuum. The valve can then be opened to apply the vacuum to the catheter to thereby aspirate at least a portion of the clot material from the blood vessel and into the catheter.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.18/167,757, filed Feb. 10, 2023, which is a continuation of U.S. patentapplication Ser. No. 17/976,711, filed Oct. 28, 2022, which is acontinuation of U.S. patent application Ser. No. 17/865,315, filed Jul.14, 2022, which is a continuation of U.S. patent application Ser. No.16/536,185, filed Aug. 8, 2019, and issued as U.S. Pat. No. 11,559,382,which claims the benefit of U.S. Provisional Patent Application No.62/718,269, filed on Aug. 13, 2018, and U.S. Provisional PatentApplication No. 62/718,248, filed on Aug. 13, 2018, each of which isherein incorporated by reference in its entirety.

TECHNICAL FIELD

The present technology relates generally to systems, methods, anddevices for the intravascular treatment of emboli and/or thrombi withina blood vessel of a human patient. In particular, some embodiments ofthe present technology relate to systems for releasing stored vacuumpressure to aspirate clot material from a blood vessel.

BACKGROUND

Thromboembolic events are characterized by an occlusion of a bloodvessel. Thromboembolic disorders, such as stroke, pulmonary embolism,heart attack, peripheral thrombosis, atherosclerosis, and the like,affect many people. These disorders are a major cause of morbidity andmortality.

When an artery is occluded by a clot, tissue ischemia develops. Theischemia will progress to tissue infarction if the occlusion persists.However, infarction does not develop or is greatly limited if the flowof blood is reestablished rapidly. Failure to reestablish blood flow canaccordingly lead to the loss of limb, angina pectoris, myocardialinfarction, stroke, or even death.

In the venous circulation, occlusive material can also cause seriousharm. Blood clots can develop in the large veins of the legs and pelvis,a common condition known as deep venous thrombosis (DVT). DVT commonlyoccurs where there is a propensity for stagnated blood (e.g., longdistance air travel, immobility, etc.) and clotting (e.g., cancer,recent surgery, such as orthopedic surgery, etc.). DVT can obstructdrainage of venous blood from the legs leading to swelling, ulcers, painand infection. DVT can also create a reservoir in which blood clots cancollect and then travel to other parts of the body including the heart,lungs, brain (stroke), abdominal organs, and/or extremities.

In the pulmonary circulation, the undesirable material can cause harm byobstructing pulmonary arteries—a condition known as pulmonary embolism.If the obstruction is upstream, in the main or large branch pulmonaryarteries, it can severely compromise total blood flow within the lungs,and therefore the entire body. This can result in low blood pressure andshock. If the obstruction is downstream, in large to medium pulmonaryartery branches, it can prevent a significant portion of the lung fromparticipating in the exchange of gases to the blood resulting in lowblood oxygen and buildup of blood carbon dioxide.

There are many existing techniques to reestablish blood flow through anoccluded vessel. Embolectomies, for example, are a surgical techniqueinvolving incising a blood vessel and placing a balloon-tipped device(such as the Fogarty catheter) at the location of the occlusion. Theballoon is then inflated at a point beyond the clot and used to withdrawthe obstructing material back to the point of incision. The obstructingmaterial is then removed by the surgeon. Although such surgicaltechniques have been useful, exposing a patient to surgery may betraumatic and best avoided when possible. Additionally, the use of aFogarty catheter may be problematic due to the possible risk of damagingthe interior lining of the vessel as the catheter is being withdrawn.

Percutaneous methods are also utilized for reestablishing blood flow. Acommon percutaneous technique is referred to as balloon angioplastywhere a balloon-tipped catheter is introduced to a blood vessel (e.g.,typically through an introducing catheter). The balloon-tipped catheteris then advanced to the point of the occlusion and inflated to dilatethe stenosis. Balloon angioplasty is appropriate for treating vesselstenosis, but it is generally not effective for treating acutethromboembolisms as none of the occlusive material is removed andrestenosis regularly occurs after dilation. Another percutaneoustechnique involves placing a catheter near the clot and infusingstreptokinase, urokinase, or other thrombolytic agents to dissolve theclot. Unfortunately, thrombolysis typically takes hours to days to besuccessful. Additionally, thrombolytic agents can cause hemorrhage, andin many patients the thrombolytic agents cannot be used at all.

Various devices exist for performing a thrombectomy or removing otherforeign material. However, such devices have been found to havestructures which are either highly complex, cause trauma to thetreatment vessel, or lack the ability to be appropriately fixed againstthe vessel. Furthermore, many of the devices have highly complexstructures that lead to manufacturing and quality control difficultiesas well as delivery issues when passing through tortuous or smalldiameter catheters. Less complex devices may allow the user to pullthrough the clot, particularly with inexperienced users, and suchdevices may not completely capture and/or collect all of the clotmaterial.

Thus, there exists a need for improved systems and methods for embolicextraction.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the present technology can be better understood withreference to the following drawings. The components in the drawings arenot necessarily to scale. Instead, emphasis is placed on illustratingclearly the principles of the present disclosure.

FIG. 1 is a partially schematic side view of a clot removal systemconfigured in accordance with the present technology.

FIG. 2 is a side view of a locking syringe configured in accordance withthe present technology.

FIG. 3A is a side view of a locking syringe configured in accordancewith the present technology.

FIG. 3B is a side view of an adaptor for connecting the locking syringeof FIG. 3A to the clot removal system of FIG. 1 configured in accordancewith the present technology.

FIG. 3C is a side view of the adaptor of FIG. 3B coupled to the lockingsyringe of FIG. 3A.

FIG. 3D is a side view of the locking syringe of FIG. 3A coupled to theclot removal system of FIG. 1 via the adaptor of FIG. 3B.

FIG. 4A is a perspective side view of another pressure source configuredin accordance with the present technology, and FIGS. 4B and 4C areenlarged schematic side views of the pressure source of FIG. 4A duringoperation.

FIG. 5 is a cross-sectional side view of an automatic release syringeconfigured in accordance with the present technology.

FIG. 6 is a perspective top view of a syringe configured in accordancewith the present technology.

FIG. 7 is a side view of an over-wire locking syringe configured inaccordance with the present technology.

FIG. 8 is a flow diagram of a process or method for operating a clotremoval system in accordance with the present technology.

FIGS. 9A-9C are side views of a proximal portion of the clot removalsystem of FIG. 1 during a clot removal procedure using the lockingsyringe of FIG. 3 in accordance with the present technology.

FIGS. 10A and 10B are schematic illustrations of a distal portion of theclot removal system of FIG. 1 during a clot removal procedure inaccordance with the present technology.

FIG. 11 is a partially schematic side view of another clot removalsystem configured in accordance with the present technology.

FIG. 12 is a flow diagram of another process or method for operating aclot removal system in accordance with the present technology.

FIGS. 13A-14C are schematic illustrations of a distal portion of theclot removal system of FIG. 11 during a clot removal procedure inaccordance with the present technology.

FIG. 15 is a flow diagram of another process or method for operating aclot removal system in accordance with the present technology.

FIGS. 16A-16E are schematic illustrations of a distal portion of theclot removal system of FIG. 11 during a clot removal procedure inaccordance with the present technology.

FIG. 17 is a partially schematic side view of another clot removalsystem configured in accordance with the present technology.

FIGS. 18A-18H are side views of a distal portion of the clot removalsystem shown of FIG. 17 during a clot removal procedure in accordancewith the present technology.

FIG. 19 is a perspective side view of a pressure source for filteringblood from aspirated clot material during a clot removal procedureconfigured in accordance with the present technology.

FIG. 20A is a partially-exploded side view of a filter device andpressure source configured in accordance with the present technology.

FIG. 20B is a perspective side view of the syringe of FIG. 20A coupledto the filter device of the FIG. 20A.

FIG. 20C is a side view of the filter device and syringe of FIG. 20Bcoupled to the clot removal system of FIG. 1 .

FIGS. 20D and 20E are side views of the syringe of FIG. 20A coupled tothe clot removal system of FIG. 1 for reintroducing blood to a patient.

FIG. 21A is a partially-exploded side view of a filter device, apressure source, and a reinfusion syringe configured in accordance withthe present technology.

FIG. 21B is a perspective side view of the filter device of FIG. 21Acoupled to the pressure source and the reinfusion syringe of FIG. 21A.

FIG. 22 is a partially-exploded side view of a filter device configuredin accordance with the present technology.

FIG. 23 is a partially-exploded side view of a filter device configuredin accordance with the present technology.

FIG. 24 is an enlarged isometric view of the clot removal system of FIG.1 configured in accordance with the present technology.

FIG. 25 is an enlarged isometric view of the clot removal system of FIG.1 configured in accordance with the present technology.

DETAILED DESCRIPTION

The present technology is generally directed to methods and systems forremoving clot material from a blood vessel of a human patient. In someembodiments, a catheter can be intravascularly positioned within a bloodvessel such that a distal portion (e.g., a distal opening) of thecatheter is positioned proximate to clot material within the bloodvessel. The catheter can be fluidly coupled to a pressure source via avalve or other fluid control device positioned outside of the patient.With the valve closed, the pressure source can be activated to charge avacuum chamber of the pressure source with a vacuum. The valve can thenbe opened to apply the vacuum to the catheter to thereby aspirate atleast a portion of the clot material from the blood vessel into thecatheter. In some embodiments, an interventional device can be deliveredthrough the catheter and used to engage the clot material before and/orafter the vacuum is applied to the catheter.

In one aspect of the present technology, the pressure source isconfigured to generate a vacuum and store the vacuum before the pressuresource is fluidly connected to the catheter. Therefore, opening thefluid control device can instantaneously or nearly instantaneously applythe stored vacuum pressure to the catheter, thereby generating suctionthroughout the catheter. In particular, the suction is applied at thedistal portion of the catheter proximate to the clot material.Pre-charging or storing the vacuum before applying the vacuum to thecatheter can generate greater suction forces (and corresponding fluidflow velocities) at and/or near the distal portion of the cathetercompared to, for example, simply activating the pressure source while itis fluidly connected to the catheter. The greater suction forcesgenerated by application of the stored vacuum can be used to aspirate orotherwise remove clot material from within a blood vessel of a humanpatient.

Although many of the embodiments are described below with respect todevices, systems, and methods for treating a pulmonary embolism, otherapplications and other embodiments in addition to those described hereinare within the scope of the technology (e.g., intravascular proceduresother than the treatment of emboli, intravascular procedures fortreating cerebral embolism, intravascular procedures for treating deepvein thrombosis (DVT), etc.). Additionally, several other embodiments ofthe technology can have different configurations, states, components, orprocedures than those described herein. Moreover, it will be appreciatedthat specific elements, substructures, advantages, uses, and/or otherfeatures of the embodiments described with reference to FIGS. 1-25 canbe suitably interchanged, substituted or otherwise configured with oneanother in accordance with additional embodiments of the presenttechnology. Furthermore, suitable elements of the embodiments describedwith reference to FIGS. 1-25 can be used as standalone and/orself-contained devices. A person of ordinary skill in the art,therefore, will accordingly understand that the technology can haveother embodiments with additional elements, or the technology can haveother embodiments without several of the features shown and describedbelow with reference to FIGS. 1-25 .

With regard to the terms “distal” and “proximal” within thisdescription, unless otherwise specified, the terms can reference arelative position of the portions of a catheter subsystem with referenceto an operator and/or a location in the vasculature. Also, as usedherein, the designations “rearward,” “forward,” “upward,” “downward,”etc. are not meant to limit the referenced component to use in aspecific orientation. It will be appreciated that such designationsrefer to the orientation of the referenced component as illustrated inthe Figures; the systems of the present technology can be used in anyorientation suitable to the user.

The headings provided herein are for convenience only and should not beconstrued as limiting the subject matter disclosed.

I. Selected Embodiments of Clot Removal Systems

FIG. 1 is a partially schematic side view of a clot treatment or clotremoval system comprising an aspiration assembly 10 (“assembly 10”)configured in accordance with an embodiment of the present technology.In the illustrated embodiment, the assembly 10 includes a cathetersubsystem 100, a tubing subsystem 120, and a pressure source 140. Thecatheter subsystem 100 includes a catheter 102 (e.g., an aspirationcatheter) comprising an elongated shaft defining a lumen 104 and havinga distal portion 103 a and a proximal portion 103 b. The cathetersubsystem 100 further includes a valve 106 that can be integral with orcoupled to the proximal portion 103 b of the catheter 102.

In the illustrated embodiment, the valve 106 includes a distal portion107 a, a proximal portion 107 b, and a lumen 109 extending therethroughfrom the distal portion 107 a to the proximal portion 107 b. The valve106 further includes a flow controller (obscured in FIG. 1 ) in thelumen 109. In some embodiments, the valve is a hemostasis valve that isconfigured to maintain hemostasis during a clot removal procedure bypreventing fluid flow in the proximal direction through the valve 106 asvarious components such as delivery sheaths, pull members, guidewires,interventional devices, other aspiration catheters (e.g., as describedin detail with reference to FIGS. 11-16E), etc., are inserted throughthe valve 106 to be delivered through the catheter 102 to a treatmentsite in a blood vessel. The valve 106 further includes a branch or sideport 108 positioned distally of the flow controller in the lumen 109 andconfigured to fluidly couple the lumen 104 of the catheter 102 to thetubing subsystem 120. In the illustrated embodiment, the valve 106includes buttons 101 that can be actuated (e.g., depressed) to open aconduit within the lumen 109. In some embodiments, the valve 106 can bea valve of the type disclosed in U.S. patent application Ser. No.16/117,519, filed Aug. 30, 2018, and titled “HEMOSTASIS VALVES ANDMETHODS OF USE,” which is incorporated herein by reference in itsentirety. In some embodiments, the proximal portion 107 b of the valve106 is further configured to be detachably coupled (e.g., via a snap-fitarrangement) to a retraction/aspiration device for aspirating the lumen104 of the catheter 102 and/or for retracting an interventional device,catheter, delivery sheath, catheter, etc., positioned within the lumen104. Specific details of such retraction/aspiration devices andassociated methods are disclosed in U.S. Pat. No. 9,526,864, filed Jun.9, 2015, and titled “RETRACTION AND ASPIRATION DEVICE FOR TREATINGEMBOLISM AND ASSOCIATED SYSTEMS AND METHODS,” which is incorporatedherein by reference in its entirety.

The tubing subsystem 120 fluidly couples the catheter subsystem 100 tothe pressure source 140. More specifically, the tubing subsystem 120 caninclude one or more tubing sections 124 (individually labeled as a firsttubing section 124 a and a second tubing section 124 b), at least onefluid control device 126 (e.g., a valve), and at least one connector 128for fluidly coupling the tubing subsystem 120 to the pressure source 140and/or other suitable components. More specifically, in the illustratedembodiment, the fluid control device 126 is a stopcock that is fluidlycoupled to (i) the side port 108 of the valve 106 via the first tubingsection 124 a and (ii) the connector 128 via the second tubing section124 b. In some embodiments, the fluid control device 126 can define alumen having a diameter (or other cross-sectional dimension) that isgreater than or equal to a diameter of the lumen 104 of the catheter102, a diameter of the first tubing section 124 a, and/or a diameter ofthe second tubing section 124 b.

The fluid control device 126 is externally operable by a user toregulate the flow of fluid therethrough and, specifically, from thelumen 104 of the catheter 102 to the pressure source 140. In otherembodiments, the fluid control device 126 can be a clamp that can beactuated (e.g., compressed or squeezed by the hand of a user) topartially or fully restrict fluid flow through the tubing section 124 aand/or the tubing section 124 b. In yet other embodiments, the fluidcontrol device 126 can be omitted and its functionality incorporatedinto the pressure source 140 (e.g., as described in detail below withreference to FIG. 5 ). In some embodiments, the fluid control device 126can include a quick-release mechanism (e.g., a spring-loaded apparatus)for rapidly opening, unclamping, etc., the fluid control device 126 to(e.g., instantaneously or nearly instantaneously) fluidly connect thepressure source 140 and the catheter 102. In some embodiments, the fluidcontrol device 126 can be opened/closed automatically (e.g., by a motor,switch, etc.). When the pressure source 140 is pre-charged with avacuum, as described in detail below, such a quick-release fluid controldevice 126 can reduce the time needed for pressure in the assembly 10 toequalize after opening of the fluid control device 126, and can therebyincrease suction forces generated at the distal portion 103 a of thecatheter 102.

In some embodiments, the connector 128 is a quick-release connector(e.g., a quick disconnect fitting) that enables rapidcoupling/decoupling of the catheter 102 and the fluid control device 126to/from the pressure source 140. In other embodiments, the tubingsubsystem 120 can have more or fewer tubing sections, connectors, and/orfluid control devices, and can have other suitable configurations. Insome embodiments, one or more of the components can be permanentlyconnected and/or integrally formed.

The pressure source 140 is configured to generate (e.g., form, create,charge, build-up, etc.) a vacuum (e.g., negative relative pressure) andstore the vacuum for subsequent application to the catheter subsystem100. Further details of suitable pressure sources are described indetail below with reference to FIGS. 2-7 . During operation of theassembly 10, a user can first close the fluid control device 126 beforeactivating the pressure source 140 to build up vacuum pressure withinthe pressure source 140 (e.g., a vacuum chamber of the pressure source140). In some embodiments, the user can control or select the volume ofthe generated vacuum. In this manner, a vacuum is charged within thepressure source 140 before the pressure source 140 is fluidly connectedto the catheter subsystem 100. To aspirate the lumen 104 of the catheter102, the user can open the fluid control device 126 to fluidly connectthe pressure source 140 to the catheter subsystem 100 and thereby applyor release the vacuum stored in the pressure source 140 to the lumen 104of the catheter 102. Opening of the fluid control device 126instantaneously or nearly instantaneously applies the stored vacuumpressure to the tubing subsystem 120 and the catheter 102, therebygenerating suction throughout the catheter 102. In particular, thesuction is applied at the distal portion 103 a of the catheter 102. Inone aspect of the present technology, pre-charging or storing the vacuumbefore applying the vacuum to the lumen 104 of the catheter 102 isexpected to generate greater suction forces (and corresponding fluidflow velocities) at and/or near the distal portion 103 a of the catheter102 compared to simply activating the pressure source 140 while it isfluidly connected to the catheter 102. As described in detail below, thesuction forces generated by application of the stored vacuum can be usedto aspirate or otherwise remove clot material from within a blood vesselof a human patient.

II. Selected Embodiments of Pressure Sources for Use with Clot RemovalSystems

As described in detail above with reference to FIG. 1 , the assembly 10of the present technology includes a pressure source (e.g., a vacuumsource, negative pressure source, etc.) configured to charge a vacuumthat can be applied to the catheter subsystem 100 to generate suctionforces for aspirating clot material from within a blood vessel. Ingeneral, the pressure source can be any suitable source or combinationof sources for generating and/or storing negative pressure. In someembodiments, the pressure source can be a pump (e.g., an electric pumpcoupled to a vacuum chamber) while, in other embodiments, the pressuresource can include one or more syringes that can be actuated orotherwise activated by a user of the assembly 10 to generate and store avacuum therein.

FIG. 2 is a side view of a pressure source 240 comprising avacuum-pressure locking syringe (“syringe 240”) configured in accordancewith the present technology. In some embodiments, the syringe 240 can beof the kind sold under the trademark “VacLok” by Merit Medical System,Inc. In the illustrated embodiment, the syringe 240 includes a plunger242 slidably and rotatably positioned within a chamber or barrel 244.The barrel 244 is shown as transparent in FIG. 2 for the sake ofclarity. The plunger 242 includes a seal 243 and a plurality of indexmembers 246 defining slots 248 between adjacent pairs thereof. A tabmember 245 projects inwardly from the interior surface of the barrel 244and is configured to be removably positioned in the slots 248 forlocking the plunger 242 in position relative to the barrel 244. In someembodiments, the barrel 244 can be made of a transparent material thatpermits a user to visualize material (e.g., clot material) within thebarrel 244 and to visualize the relative position between the slots 248and tab member 245 for locking the syringe 240.

Referring to both FIGS. 1 and 2 together, the syringe 240 furtherincludes a tip 247 for coupling the syringe 240 to the tubing subsystem120. In the illustrated embodiment, the tip 247 is a standard luerconnector that can be coupled to the connector 128 via one or moresuitable adaptors. The tip 247 further defines a lumen or bore 249having an inner diameter D₁. In some embodiments, the diameter D₁ isabout 0.103″, or about 0.080″ to about 0.200″, or about 0.100″ to about0.150″, or about 0.100″ to about 0.110″. In some embodiments, the innerdiameter D₁ is about 14 French.

During operation of the assembly 10, a user can first close the fluidcontrol device 126 and then grip the plunger 242 and/or the barrel 244to withdraw (e.g., retract) the plunger 242 at least partially out ofthe barrel 244 to thereby generate a vacuum in the barrel 244. Once theuser has withdrawn the plunger 242 to a sufficient or desired volume,the user can lock the plunger 242 by rotating the plunger 242 relativeto the barrel 244 such that the tab member 245 is positioned within acorresponding one of the slots 248. In other embodiments, the syringe240 may not be a locking syringe, and the user can instead hold theplunger 242 in position relative to the barrel 244. Moreover, the usercan control the volume of the vacuum—by withdrawing the plunger 242 moreor less—to provide a desired amount or level of suction/aspiration uponopening of the fluid control device 126. In some embodiments, thesyringe has a volume of about 60 cc or less than about 60 cc.

FIG. 3A is a side view of a pressure source 340 comprising avacuum-pressure locking syringe (“syringe 340”) configured in accordancewith the present technology. The syringe 340 can have some featuresgenerally similar to the features of the syringe 240 described abovewith reference to FIG. 2 . For example, the syringe 340 includes aplunger 342 slidably and rotatably positioned within a barrel 344, andthe plunger 342 includes a plurality of index members 346 defining slots348 between adjacent pairs thereof. The barrel 344 is shown astransparent in FIG. 3A (and FIG. 3C) for the sake of clarity. Whilewithdrawing the plunger 342, a user can lock the plunger 342 at aspecified volume by rotating the plunger 342 relative to the barrel 344such that a tab member 345 on the interior surface of the barrel 344 ispositioned within a corresponding one of the slots 348. In someembodiments, the syringe 340 has a maximum volume of about 60 cc orgreater than 60 cc.

In the illustrated embodiment, the syringe 340 includes a large-bore tip347, such as a Toomey tip, defining an inner lumen or bore 349. In someembodiments, the bore 349 can have an inner diameter D₂ that is greaterthan or equal to the largest inner diameter of the assembly 10 (e.g., ofthe catheter 102 and tubing subsystem 120). In certain embodiments, thetip 347 can be about 26 French or greater. Accordingly, referring toFIGS. 2 and 3A together, the diameter D₂ can be greater than thedimension D₁. For example, the dimension D₂ can be about two, three,four, or more times greater than the diameter D₁.

FIG. 3B is a side view of an adaptor 350 for connecting the syringe 340to the catheter subsystem 100 configured in accordance with the presenttechnology. FIG. 3C is a side view of the adaptor 350 coupled to thesyringe 340, and FIG. 3D is a side view of the syringe 340 coupled tothe tubing subsystem 120 via the adaptor 350. The adaptor 350 is shownas partially transparent in FIG. 3C for the sake of illustration.Referring to FIG. 3B, the, the adaptor 350 includes (i) a first portion351 defining a first lumen or bore 352 having an inner diameter D3, (ii)a second portion 353 defining a second lumen or bore 354, and (iii) astepped surface or interface 355 between the first and second portions351, 353. The first portion 351 can further include a seal 357 such asan O-Ring around an exterior surface thereof.

Referring to FIGS. 3A-3D together, the second bore 354 of the adaptor350 is configured to removably receive the tip 347 of the syringe 340therein. In some embodiments, the tip 347 can be snuggly received in thesecond bore 354 via an interference fit. In some embodiments, a seal(e.g., an O-ring) can be positioned between an exterior surface of thetip 347 and an interior surface of the second bore 354. In otherembodiments, the syringe 340 can be permanently coupled or integrallyformed with the adaptor 350. The first portion 351 of the adaptor 350 isconfigured to be removably positioned within the connector 128 of thetubing subsystem 120 to fluidly couple the syringe 340 to the tubingsubsystem 120. In some embodiments, the first portion 351 of the adaptor350 can be pushed into the connector 128 until the interface 355 abutsthe connector 128. When the first portion 351 of the adaptor 350 ispositioned within the connector 128, the seal 357 seals the interfacebetween the connector 128 and the adaptor 350.

The diameter D3 of the first bore 352 of the adaptor 350 can be selectedto be about the same as or greater than the greatest inner diameter ofthe assembly 10 (e.g., of the catheter 102 and the tubing subsystem120). For example, the catheter 102 can be about 9 French or greater,and the diameter D3 can be selected to be larger than the size of thecatheter 102. Accordingly, when the fluid control device 126 is open,the continuous lumen between the catheter 102 and the syringe 340 canhave a generally constant diameter and/or does not contain any narrowingat the interface between the syringe 340 and the tubing subsystem 120.That is, the adaptor 350 can connect the syringe 340 and the tubingsubsystem 120 without any restriction or narrowing of the fluid path. Incontrast, a standard luer connector (e.g., the syringe 240) can onlyprovide a continuous lumen for catheters of about 8 French or smaller.Any narrowing of the fluid pathway between the catheter 102 and thesyringe 340 can reduce the volumetric flow rate (e.g., suction forcesand fluid velocities) that can be generated when a vacuum stored in thesyringe 340 is applied to the catheter 102.

In general, the syringe 340 and the adaptor 350 can reduce the fluidresistance in the assembly 10 and therefore facilitate a more rapidpressure equalization in the assembly 10 when the fluid control device126 is opened to apply the charged vacuum to the catheter 102. In someembodiments, for example, when the syringe 240 (FIG. 2 ) is charged witha 60 cc vacuum and the fluid control device 126 is opened, the pressurein the assembly 10 can take about 1-2 seconds to equalize. In contrast,when the syringe 340 is charged with a 60 cc vacuum and the fluidcontrol device 126 is opened, the pressure in the assembly 10 can takeless than about 1 second (e.g., about 0.5 seconds) to equalize. Morespecifically, Table 1 illustrates representative pressure equalizationtimes and associated flow rates when the syringe 240 is coupled to a 20French catheter (i.e., the catheter 102). Table 2 illustratesrepresentative pressure equalization times and associated flow rateswhen the syringe 340 and the adaptor 350 are coupled to a 20 Frenchcatheter (i.e., the catheter 102).

TABLE 1 Pressure Equalization Time (seconds) Flow Rate (cc/sec) 2.0 30.01.9 31.6 1.8 33.3 1.7 35.3 1.6 37.5 1.5 40.0 1.4 42.9 1.3 46.2

TABLE 2 Pressure Equalization Time (seconds) Flow Rate (cc/sec) 0.9 66.70.8 75.0 0.7 85.7 0.6 100.0 0.5 120.0 0.4 150.0 0.3 200.0 0.2 300.0 0.1600.0

In each instance, the syringe 340 provides for relatively fasterequalization times and correspondingly greater flow rates. It isexpected that the more rapid pressure equalization and flow ratesprovided by the syringe 340 will provide correspondingly greater suctionforces at the distal portion 103 a of the catheter 102. That is, ingeneral, it is expected that increasing the bore size of a syringe usedto provide vacuum pressure will provide greater suction forces over asmaller period of time (e.g., will provide a larger vacuum impulse). Insome embodiments, the greater suction forces can facilitate the removalof clot material from a blood vessel of a patient even where the clotmaterial is strongly lodged or attached within the blood vessel (e.g., achronic clot).

Moreover, as shown in FIG. 3D, the adaptor 350 can couple the syringe340 to the connector 128 without the need for any intervening tubingsections or additional adaptors. This arrangement can minimize the totallength, volume, etc., of the components fluidly coupling the catheter102 to the syringe 340. It is expected that the magnitude of suctionforces generated at the distal portion 103 a of the catheter 102—e.g.,when a vacuum charged in the syringe 340 is applied to the catheter 102by opening of the fluid control device 126—is proportional to the lengthof the fluid path between the pressure source 340 and catheter 102.Thus, operation of the assembly 10 with the syringe 340 and adaptor 350is expected to increase the suction forces generated at the distalportion 103 a of the catheter 102. In some embodiments, the greatersuction forces can facilitate the removal of clot material from a bloodvessel of a patient even where the clot material is strongly lodged orattached within the blood vessel (e.g., a chronic clot).

FIG. 4A is a side perspective view a pressure source 400 including thesyringe 340 (“primary syringe 340”) shown in FIGS. 3A-3D and a secondarysyringe 460 configured in accordance with the present technology. Thesecondary syringe 460 can include a plunger 462 slidably positionedwithin a chamber or barrel 464. The primary and secondary syringes 340,460 can have the same volume or different volumes. In the illustratedembodiment, a tip 463 of the secondary syringe 460 is coupled to a firstone-way valve (e.g., a check valve) 470 via a coupling member 465, suchas a tube. The first one-way valve 470 is configured to fluidly connectthe secondary syringe 460 to the ambient environment or another devicecoupled to the first one-way valve 470. A second one-way valve (e.g., acheck valve) 472 spans between and is configured to fluidly connect theprimary syringe 340 to the secondary syringe 460. More specially, in theillustrated embodiment the second one-way valve 472 is connected betweenthe first portion 351 of the adaptor 350 and the coupling member 465. Inother embodiments, the second one-way valve 472 can couple the primaryand secondary syringes 340, 460 in different manners. For example, thesecond one-way valve 472 can span between and directly connect thebarrels 344,464. The primary and secondary syringes 340, 460 can becoupled or fastened together via one or more connectors 474 that fix thepositions of the barrel 344, 464 relative to one another.

In some embodiments, the second one-way valve 472 is a normally-opencheck valve configured to (i) permit fluid (e.g., air) flow from theprimary syringe 340 and the adaptor 350 to the secondary syringe 460 and(ii) inhibit fluid flow in the opposite direction from the secondarysyringe 460 into the primary syringe 340. In some embodiments, thesecond one-way valve 472 has a cracking (e.g., opening) pressure ofabout 0 psi. In one aspect of the present technology, this arrangementmaximizes the magnitude of the vacuum that can be charged within theprimary syringe 340. That is, the cracking pressure of the secondone-way valve 472 does not reduce the effective vacuum within theprimary syringe 340. In other embodiments a normally-closed or othertype of valve could be used for the second one-way valve 472. However,in such embodiments the vacuum efficiency of the pressure source 400would be reduced by the cracking pressure of the second one-way valve472. Similarly, the first one-way valve 470 can be a check valveconfigured to (i) permit fluid flow from the secondary syringe 460 tothe ambient environment (or other device) and (ii) inhibit fluid flow inthe opposite direction from the ambient environment into the secondarysyringe 460.

FIGS. 4B and 4C are enlarged schematic side views of the pressure source400 during operation. More specifically, FIGS. 4B and 4C illustratefluid flow paths through the first and second one-way valves 470, 472during retraction and advancement, respectively, of the plunger 462through the barrel 464 of the secondary syringe 460. Referring first toFIGS. 4A and 4B together, during retraction/withdrawal of the plunger462, (i) the first one-way valve 470 is closed to inhibit fluid fromflowing into the secondary syringe 460 while (ii) the second one-wayvalve is open 472 to permit fluid to flow from the primary syringe 340,the catheter subsystem 100 (FIG. 1 ), and/or the tubing subsystem 120(FIG. 1 ) into the secondary syringe 460. This flow path is indicated bythe arrows R in FIG. 4B. Referring to FIGS. 4A and 4C together, duringadvancement of the plunger 462, (i) the first one-way valve 470 is opento permit fluid flow (e.g., fluid expulsion) from the secondary syringe460 to the ambient environment (or other device) while (ii) the secondone-way valve 472 is closed to inhibit fluid flow from the secondarysyringe 460 into (e.g., back into) the primary syringe 360, the cathetersubsystem 100, and/or the tubing subsystem 120. This flow path isindicated by the arrows A in FIG. 4C.

Referring to FIGS. 1 and 3A-4C together, the pressure source 400 can becoupled to the tubing subsystem 120 by coupling the primary syringe 340to the connector 128 (e.g., as shown in FIG. 3D). When the pressuresource is coupled to the tubing subsystem 120, retraction of the plunger462 of the secondary syringe 460 evacuates an evacuatable volume of theassembly 10. For example, when the fluid control device 126 is closed,retraction of the plunger 462 of the secondary syringe 460 evacuatesfluid, through the second one-way valve 472, from (i) the primarysyringe 340 (e.g., from the barrel 344, the tip 347, and/or the adaptor350) and (ii) the portion of the tubing subsystem 120 between the fluidcontrol device 126 and the primary syringe 340. This can enable agreater charged/stored vacuum to be generated for subsequent applicationto the catheter subsystem 100 for aspirating clot material. In someembodiments, the plunger 462 of the secondary syringe 460 can bewithdrawn/advanced (e.g., “cycled”) one or more times before withdrawingthe plunger 342 of the primary syringe 340 to evacuate air from (i) thetip 347 of the primary syringe 340 and/or (ii) the portion of the tubingsubsystem 120 between the fluid control device 126 and the tip 347. Inother embodiments, the plunger 462 of the secondary syringe 460 canalternatively or additionally be withdrawn after withdrawing the plunger342 of the primary syringe 340 to further evacuate the barrel 344 of theprimary syringe 340. In some embodiments, the plunger 462 can be cycledwhen the fluid control device 126 is open to, for example, facilitatethe removal of clot material stuck or clogged within the cathetersubsystem 100. That is, cycling the secondary syringe 460 when the fluidcontrol device 126 is open can generate vacuum pressure and suction inthe catheter 102 to aid in the aspiration/removal of clot material.

In some embodiments, the volumes of the primary and secondary syringes340, 460 can be selected based on one or more desired characteristics ofa clot removal procedure using the pressure source 400. For example, thesecondary syringe 460 can have a larger volume than the primary syringe340 to permit a high vacuum to be charged within the primary syringe 340while also limiting blood loss from the patient.

In one aspect of the present technology, the pressure source 340 permitsa greater vacuum to be generated without increasing the volume of theprimary syringe 340. For example, the vacuum generated by the primarysyringe 340 alone is directly proportional to the volume of the primarysyringe 340. Thus, to generate a greater vacuum using the primarysyringe 340 alone, the volume of the primary syringe 340 must beincreased. In contrast, inclusion of the secondary syringe 460 in thepressure source 400 and the configuration of the first and secondone-way valves 470, 472 allows the (e.g., maximum) generated vacuum tobe independent of the volume of the primary syringe 340. Therefore, forexample, the generated vacuum can be increased without correspondinglyincreasing the volume of blood withdrawn from the patient when applyingthe vacuum to the catheter subsystem 100.

In some embodiments, (e.g., as described in greater detail below withreference to FIG. 19 ), the primary syringe 340 of the pressure source400 can be replaced with a simple pressure vessel or other volume, suchas a canister, barrel, tube, etc. In such embodiments, a vacuum can begenerated in the canister simply by cycling the secondary syringe 460one or more times. In some embodiments, the secondary syringe 460 cancomprise a pump or vacuum source other than a syringe. Likewise, thesecondary syringe 460 or other vacuum source can be fluidly coupled tothe primary syringe 340 in other manners (e.g., via a differentarrangement of check valves) to produce the same or similar flowpatterns as shown in FIGS. 4B and 4C. Moreover, in some embodiments thefirst and second one-way valves 470, 472 can be other types of flowcontrol devices that are mechanically activated/deactivated (e.g.,opened and closed) rather than passively operated via pressuredifferentials within the pressure source 400. For example, the flowcontrol devices 470, 472 can be mechanically coupled to the plunger 462of the secondary syringe 460 such that cycling the plunger 462activates/deactivates the flow control devices 470, 472 to operate thepressure source 400 in the manner illustrated in FIGS. 4B and 4C.

FIG. 5 is a side cross-sectional view of a pressure source 540comprising an automatic release syringe (“syringe 540”) configured inaccordance with the present technology. In general, the syringe 540 isconfigured to automatically apply a charged vacuum of a selected volumeto the catheter subsystem 100 without requiring the actuation of anintervening fluid control device, such as the fluid control device 126shown in FIG. 1 . The syringe 540 can have some features generallysimilar to the features of the syringes 240, 340 described in detailabove with reference to FIGS. 2 and 3A-3D. For example, the syringe 540includes a first plunger 542 slidably positioned within a chamber orbarrel 544. The first plunger 542 further includes a first seal 543 thatengages an interior surface of the barrel 544 such that a vacuum isformed within the barrel 544 as the first plunger 542 is withdrawnthrough the barrel 544. Likewise, referring to both FIGS. 1 and 5together, the syringe 540 includes a tip 547 (e.g., a Toomey tip) forcoupling the syringe 540 to the tubing subsystem 120 (e.g., via a Toomeytip adaptor) and defining a bore 549. In some embodiments, the bore 549has a relatively large diameter selected to provide rapid pressureequalization in the assembly 10 after a vacuum stored in the syringe 540is released.

The first plunger 542 can further include (i) a grip portion 541configured to be engaged by a user for retracting the first plunger 542and (ii) a lumen 581 extending lengthwise therethrough. In theillustrated embodiment, a plunger assembly 582 is slidably positionedwithin and extends through the lumen 581 of the first plunger 542. Theplunger assembly 582 includes (i) a second plunger 583 and (ii) arelease member 584 slidably and/or rotatably positioned within a lumen585 of the second plunger 583. The release member 584 includes anengagement member 586 configured to engage the grip portion 541 of thefirst plunger 542 when the first plunger 542 is withdrawn from thebarrel 544. The second plunger 583 includes a second seal 587 configuredto engage and seal an interior surface of the bore 549 of the syringe540 to enable a vacuum to be formed in the barrel 544 as the firstplunger 542 is withdrawn through the barrel 544. That is, the secondseal 587 can seal (e.g., fluidly disconnect) the barrel 544 of thesyringe from the tubing subsystem 120 and the catheter subsystem 100. Insome embodiments, the syringe 540 can further include an O-ring 579 orother suitable component for sealing an interface between the first andsecond plungers 542, 582 to maintain the vacuum formed within the barrel544, while also permitting the first plunger 542 to move (e.g.,translate) relative to the second plunger 583.

The plunger assembly 582 further includes a locking mechanism (notshown) configured to permit/inhibit the release member 584 from movinglongitudinally relative to the second plunger 583. In some embodiments,for example, rotation of the release member 584 in a first directionrelative to the second plunger 583 can lock the two components inposition, while rotation of the release member 584 in a second directionrelative to the second plunger 583 can unlock the two components so thatthe release member 584 can be withdrawn or pushed into the lumen 585 ofthe second plunger 583. In other embodiments, the release member 584 andthe second plunger 583 can be integrally formed or permanently lockedtogether.

The plunger assembly 582 enables (i) a user of the syringe 540 to selecta desired volume for a vacuum to be formed in the syringe 540 and (ii)the automatic release or application of a generated vacuum via opening(e.g., unplugging) of the bore 549. Specifically, during operation ofthe syringe 540, a user can first unlock the release member 584 andslide the release member 584 to a position corresponding to a desiredvacuum volume. For example, the release member 584 can have tick marks588 or other indicia along its length that correspond to a volume of thesyringe 540 (e.g., a vacuum chamber volume). After selecting a desiredvolume, the user can lock the release member 584 relative to the secondplunger 583 (e.g., by rotating the release member 584) to inhibitrelative movement of the two components. After locking the releasemember 584, the user can grasp the grip portion 541 to retract the firstplunger 542 relative to the barrel 544 and the plunger assembly 582 togenerate a vacuum within the barrel 544 between the first and secondseals 543, 587. When the first plunger 542 has been retracted to thedesired volume, the grip portion 541 engages the engagement member 586of the release member 584 such that further retraction of the firstplunger 542 simultaneously retracts the plunger assembly 582. As theplunger assembly 582 is retracted, the second seal 587 of the secondplunger 583 is pulled out of the bore 549, thereby releasing the vacuumstored in the barrel 544. In this manner, the syringe 540 provides forthe automatic release of charged vacuum pressure at a specified volumeand with a single retraction of the first plunger 542. Put differently,the syringe 540 has a built-in fluid control device and thus eliminatesthe need for a separate fluid control device 126 and/or an additionalstep for opening the fluid control device 126.

FIG. 6 is a top perspective view of a pressure source 640 comprising asyringe (“syringe 640”) configured in accordance with the presenttechnology. The syringe 640 can include some features generally similarto the features of the syringes 240, 340, and 540 described in detailabove with reference to FIGS. 2-3D and 5 . For example, the syringe 640includes a plunger 642 slidably positioned within a barrel 644, and atip 647 (e.g., a large-bore tip). In the illustrated embodiment, thesyringe 640 further includes a lever or handle 690 operably coupled tothe plunger 642. The handle 690 provides mechanical leverage forwithdrawing the plunger 642 to create a vacuum within the barrel 644.More specifically, the handle 690 can be coupled to a crossbar 691 thatrotates relative to the plunger 642 via actuation (e.g., rotation) ofthe handle 690. The crossbar 691 can be coupled to a gear (obscured inFIG. 6 ) configured to engage a track 692 on the plunger 642.Accordingly, rotation of the handle 690 in a first direction retractsthe plunger 642 relative to the barrel 644 to charge a vacuum in thebarrel 644. And, rotation of the handle 690 in a second (e.g., opposite)direction advances the plunger 642 into the barrel 644 to, for example,expel fluid, material, etc., from the barrel 644.

In one aspect of the present technology, the handle 690 providesadditional mechanical leverage relative to a standard syringe, and canthus reduce the force (e.g., strain, energy, etc.) required by a user ofthe syringe 640 to form a vacuum in the syringe 640. Therefore, use ofthe syringe 640 can reduce the time needed to remove clot material withthe assembly 10. In some embodiments, the syringe 640 can have a volumegreater than 60 cc (e.g., greater than 80 cc, greater than 100 cc,greater than 120 cc, greater than 140 cc, etc.). In a particularembodiment, for example, the syringe 640 can have a volume of about 140cc. With such large volumes, it may be difficult for some users tomanually retract the plunger 642 without the additional mechanicalleverage provided by the handle 690. Thus, the syringe 640 can enablethe use of larger volume syringes that can generate correspondinglygreater suction forces in the catheter subsystem 100.

Referring again to FIG. 1 , it is expected that less tortuous (e.g.,more linear) fluid paths between the pressure source 140 and thecatheter subsystem 100 will produce greater suction forces andcorresponding fluid velocities at the distal portion 103 a of thecatheter 102 when stored vacuum pressure is applied to the cathetersubsystem 100. Accordingly, in some embodiments the side port 108 of thevalve 106 can be formed to have an angle A that is less than about 90°,less than about 75°, less than about 60°, less than about 45°, less thanabout 30°, less than about 15° etc. Reducing the relative angle betweenthe side port 108 and the lumen 109 of the valve 106 (and thus the lumen104 of the catheter 102) reduces the tortuosity of the fluid pathbetween the pressure source 140 and the catheter 102. Moreover, in someembodiments, the pressure source 140 can be coupled to the proximalportion 107 b of the valve 106 instead of or in addition to the sideport 108 to provide a more linear fluid path between the pressure source140 and the catheter 102. For example, FIG. 24 is an enlarged isometricview of the assembly 10 showing the pressure source 340 coupled directlyto the proximal portion 107 b of the valve rather than to the connector128 of the tubing subsystem 120 and the side port 108 of the valve 106.Although the pressure source 340 is illustrated in FIG. 24 , any of thepressure sources described in detail above with reference to FIGS. 2-6can be configured to be coupled to the proximal portion 107 b of thevalve 106 rather than the side port 108. In other embodiments, the sideport 108 can be omitted and the valve 106 and the tubing subsystem 120can be coupled to the catheter 102 via a Y-connector. For example, FIG.25 is an enlarged isometric view of the assembly 10 showing the valve106 and the tubing subsystem 120 coupled to the catheter 102 via aY-connector 2590. In yet other embodiments, the tubing system 120 islinearly coupled to the catheter 102, and the valve 106 protrudes at anangle from the catheter 102.

In some embodiments, however, a guidewire or other component ispositioned within the valve 106 during the duration of a clot removalprocedure (e.g., for delivering interventional devices to a treatmentsite within a patient). Accordingly, in some embodiments, to facilitatecoupling of the pressure source 140 to the proximal portion 107 b of thevalve 106—even when a guidewire is inserted therethrough—the pressuresource 140 can be a syringe configured for over-wire delivery. Forexample, FIG. 7 is a side view of a pressure source 740 comprising avacuum-pressure locking syringe (“syringe 740”) configured in accordancewith the present technology for delivery and operation over a guidewire794. The syringe 740 can have some features generally similar to thefeatures of the syringe 340 described in detail above with reference toFIG. 3 . For example, the syringe 740 includes a plunger 742 slidablyand rotatably positioned within a barrel 744. The barrel 744 is shown astransparent in FIG. 7 for the sake of clarity. In the illustratedembodiment, the plunger 742 includes a lumen 796 (shown in broken lines)extending longitudinally therethrough. The guidewire 794 can be insertedthrough the lumen 796 of the plunger 742 such that the syringe 740 canbe advanced over the guidewire 794 for attachment to the proximalportion 107 b of the valve 106. The syringe 740 can further include oneor more sealing components (e.g., valves, O-rings, etc.; not shown) formaintaining a seal between the guidewire 794 and the plunger 742 topermit build-up and storage of a vacuum in the barrel 744.

In general, one skilled in the art will understand that the variousembodiments of pressure sources disclosed herein may be combined to, forexample, include multiple pressure sources or pressure sources havingdifferent components or combinations of components. For example, in someembodiments the secondary syringe 460 (FIGS. 4A-4C) can be coupled viaone or more one-way valves to the syringes 240, 540, 640 or 740 (FIGS. 2and 5-7 , respectively) to generate additional vacuum. In someembodiments, multiple pressure sources can be coupled to the catheter102 via the tubing subsystem 120 and/or via the valve 106. Moreover, theindividual pressure sources can be the same or different, and can becoupled to the catheter subsystem 100 via a single fluid control device,such as the fluid control device 126, or can be coupled to the cathetersubsystem 100 via separate fluid control devices. Therefore, the profileof the vacuum applied to the catheter 102 can be selected or adjusted byusing multiple different pressure sources. For example, a specificvacuum profile can depend at least on (i) the individual characteristicsof the multiple pressure sources (e.g., volume, bore-size, etc.), (ii)the manner in which the pressure sources are coupled to the cathetersubsystem 100 (e.g., via individual valves, via the same valve, etc.),and (iii) the timing of the application or release of the vacuum of eachpressure source to the catheter subsystem 100 (e.g., staggered release,simultaneous release, etc.). As one example, in some embodiments, thesyringe 240 (FIG. 2 ) and the syringe 340 (FIG. 3 ) can both be coupledto the tubing subsystem 120 via, for example, a Y-connector. Aftercharging both syringes 240, 340 with vacuum pressure, opening the fluidcontrol device 126 can simultaneously apply the combined vacuum to thecatheter 102. The larger-bored syringe 340 can provide a short butpowerful impulse of vacuum pressure, while the smaller-bored syringe 240can provide a longer and more sustained vacuum pull. This combinationcan apply a large, fast-acting suction force to dislodge and captureclot material in the catheter 102, and simultaneously apply a moresustained suction force to capture more clot material.

III. Selected Embodiments of Methods of Clot Removal

FIG. 8 is a flow diagram of a process or method 800 for operating a clotremoval system including the assembly 10 to remove clot material fromwithin a blood vessel (e.g., a pulmonary blood vessel) of a humanpatient in accordance with the present technology. FIGS. 9A-9C are sideviews of a proximal portion of the assembly 10, and FIGS. 10A and 10Bare schematic illustrations of a distal portion of the assembly 10,during a clot removal procedure in accordance with embodiments of thepresent technology. In particular, FIGS. 9A-9C are side views of theassembly 10 including the syringe 340 and adaptor 350 (FIGS. 3A-3D), andFIGS. 10A and 10B are side views of the catheter 102 with the distalportion 103 a of the catheter 102 positioned proximate to an embolism orclot material PE within a blood vessel BV (e.g., a pulmonary bloodvessel). Although some features of the method 800 are described in thecontext of the embodiments shown in FIGS. 1, 3A-3D, and 9A-10B for thesake of illustration, one skilled in the art will readily understandthat the method 800 can be carried out using other suitable systemsand/or devices described herein. In particular, although described inthe context of the syringe 340, the method 800 can be carried out usingany one or combination of the pressure sources described in detail abovewith reference to FIGS. 2-7 .

At block 802, the method 800 includes positioning the distal portion 103a of the catheter 102 proximate to clot material within a blood vesselof a human patient (e.g., at a treatment site). For example, in theembodiment illustrated in FIG. 10A, a distal terminus of the distalportion 103 a of the catheter 102 is positioned proximate to a proximalportion of the clot material PE. It is expected that reducing thedistance between the distal terminus of the catheter 102 and theproximal portion of the clot material PE—without contacting the clotmaterial PE with the catheter 102—will maximize the suction forces onthe clot material PE when the fluid control device 126 is opened. It isalso expected that reducing the distance (e.g., clearance) between theinner diameter of the blood vessel BV and the outer diameter of thecatheter will maximize the suction forces on the clot material PE.However, in other embodiments, the distal terminus of the catheter 102can be positioned at least partially within the clot material PE, or thedistal terminus of the catheter 102 can be positioned distal of the clotmaterial PE.

Access to the pulmonary vessels can be achieved through the patient'svasculature, for example, via the femoral vein. In some embodiments, thecatheter subsystem 100 can include an introducer (e.g., a Y-connectorwith a hemostasis valve; not shown) that can be partially inserted intothe femoral vein. A guidewire (not shown) can be guided into the femoralvein through the introducer and navigated through the right atrium, thetricuspid valve, the right ventricle, the pulmonary valve, and into themain pulmonary artery. Depending on the location of the embolism, theguidewire can be guided to one or more of the branches of the rightpulmonary artery and/or the left pulmonary artery. In some embodiments,the guidewire can be extended entirely or partially through the clotmaterial PE. In other embodiments, the guidewire can be extended to alocation just proximal of the clot material PE. After positioning theguidewire, the catheter 102 can be placed over the guidewire andadvanced (e.g., as indicated by arrow A1) to a position proximate to theclot material PE as illustrated in FIG. 10A.

In some embodiments, to confirm the position of the distal portion 103 aof the catheter 102, a contrast agent can be injected through thecatheter 102 and viewed using fluoroscopic imaging techniques, as isknown in the art. In some embodiments, the valve 106 can be opened todetermine the position of the distal portion 103 a of the catheter 102relative to the clot material PE. For example, the activation buttons101 can be depressed to open the lumen 109 of the valve 106. If there issubstantially no back-bleeding through the valve 106, the operator candetermine that the distal portion 103 a of the catheter 102 is fullyengaged with the clot material PE. Conversely, if there is someback-bleeding through the valve 106, the operator can determine that thedistal portion 103 a of the catheter is not fully engaged with the clotmaterial PE. Accordingly, to locate the distal portion 103 a of thecatheter 102 just proximal of the clot material PE, the operator can (i)first determine that distal portion 103 a of the catheter is fullyengaged with the clot material PE by activating the valve 106 anddetecting no back-bleeding and (ii) then reposition the catheter 102(e.g., by withdrawing the catheter 102 proximally) and activate thevalve 106 until back-bleeding is detected—thereby confirming that thedistal portion 103 a of the catheter 102 is positioned proximal of theclot material PE. In some embodiments, the valve 106 can be openedduring retraction of the catheter 102 until back-bleeding is detected.In other embodiments, the valve 106 can be closed during retraction ofthe catheter 102, and the catheter 106 can be retracted a set (e.g.,predetermined) distance before the valve 106 is opened again. In oneaspect of the present technology, determining the position of the distalportion 103 a of the catheter 102 via activation of the valve 106 can beused when it is difficult to determine the position of the catheter 102via radiographic techniques. In contrast, many conventional hemostasisvalves cannot be activated in this manner.

In some embodiments, the guidewire can then be withdrawn while, in otherembodiments, the guidewire can remain and can be used to guide othercatheters (e.g., delivery catheters, additional aspiration catheters,etc.), interventional devices, etc., to the treatment site. It will beunderstood, however, that other access locations into the venouscirculatory system of a patient are possible and consistent with thepresent technology. For example, the user can gain access through thejugular vein, the subclavian vein, the brachial vein, or any other veinthat connects or eventually leads to the superior vena cava. Use ofother vessels that are closer to the right atrium of the patient's heartcan also be advantageous as it reduces the length of the instrumentsneeded to reach the pulmonary embolism.

At block 804, the method 800 includes coupling a pressure source (e.g.,the syringe 340) to the catheter 102 via the fluid control device 126.For example, in the embodiment illustrated in FIG. 9A, the tip 347(shown in FIGS. 3A and 3C but obscured in FIG. 9A) of the syringe 340can be coupled to the connector 128 via the adaptor 350. Once thesyringe 340 is coupled to the catheter 102, (i) opening the fluidcontrol device 126 fluidly connects the syringe 340 to the lumen 104 ofthe catheter 102, and (ii) closing the fluid control device 126 fluidlydisconnects the syringe 340 from the lumen 104 of the catheter 102. Thefluid control device 126 is in an open position in FIG. 9A.

At block 806, the method 800 includes activating the syringe 340 togenerate a vacuum while the fluid control device 126 is closed. Forexample, as shown in FIG. 9B, the user can first actuate the fluidcontrol device 126 to close the fluid control device 126, and thenretract the plunger 342 to generate a vacuum in the barrel 344 of thesyringe 340. The user can subsequently lock the plunger 342 relative tothe barrel 344, as described in detail above, to store or maintain avacuum of known volume in the syringe 340. In this manner, the syringe340 can be pre-charged with a vacuum before the vacuum is applied to thecatheter 102. In contrast, many conventional aspiration techniquesinclude activating a negative pressure source (e.g., a pump, a syringe,etc.) while the pressure source is fluidly connected to a lumen to beaspirated. In some embodiments, when the pressure source 400 with thesecondary syringe 460 (FIGS. 4A-4C) is used with the primary syringe340; the secondary syringe 460 can be cycled one or more times before orafter retracting the plunger 342 to increase the vacuum pressure.

At block 808, the method 800 includes opening the fluid control device126 to apply the vacuum to the lumen 104 of the catheter 102. Forexample, with reference to FIG. 9C, the user can actuate (e.g., twist ahandle of) the fluid control device 126 to open the fluid control device126 and apply the vacuum stored in the syringe 340 to the cathetersubsystem 100. As shown in FIG. 10B, application of the vacuum causessuction at the distal tip 103 a of the catheter 102 (e.g., as indicatedby arrow A2) that aspirates at least a portion of the clot material PEfrom the blood vessel BV and into the lumen 104 of the catheter 102. Insome embodiments, opening the fluid control device 126 instantaneouslyor nearly instantaneously generates suction at the distal portion 103 aof the catheter 102. In certain embodiments, application of the vacuumcan generate suction for less than about 1 second (e.g., about 0.5second), substantially less than about 1 second (e.g., about 0.3 second,about 0.1 second, etc.) less than about 2 seconds, or greater than about2 seconds—until the pressure in the assembly 10 equalizes. In someembodiments, depending on the volume of the vacuum chamber formed in thesyringe 340 and the dimensions of the catheter subsystem 100 and thetubing subsystem 120 (e.g., where the syringe 340 has a volume that isgreater than or about equal to a volume of the catheter subsystem 100),at least some of the clot material PE can be aspirated entirely throughthe lumen 104 of the catheter 102 and into the barrel 344 of the syringe340. In some such embodiments, the user can determine whether subsequentsteps for treating the clot material PE are necessary or desirable byvisualizing the amount of clot material collected in the syringe 340.FIG. 9C, for example, illustrates the syringe 340 and the tubingsubsystem 120 after the fluid control device 126 has been opened toapply the vacuum stored in the syringe 340 to the catheter 102. In theillustrated embodiment, some of the clot material PE is visible in thesyringe 340.

In some embodiments, the fluid control device 126 or another fluidcontrol device can be intermittently operated to provide discrete burstsof suction. For example, the fluid control device 126 can be quicklyopened and closed to provide a first burst of suction (e.g., vacuumrelease) without fully equalizing the pressure in the assembly 10. Thefluid control device 126 can then be opened again to provide a secondburst of suction, or opened and closed repeatedly to provide a desiredsuction pattern. In some embodiments, the assembly 10 can bespecifically configured to facilitate the application of multiple burstsof suction. For example, (i) the fluid control device 126 can bespring-loaded, electronically controlled, etc., to rapidly open andclose the valve, and/or (ii) the pressure source 140 can have a largevacuum chamber and/or small bore size to increase the time required forpressure in the assembly 10 to equalize (e.g., to increase a dischargetime of the pressure source 140).

Sometimes, as shown in FIG. 10B, discharging the vacuum stored in thepressure source to aspirate the lumen 104 of the catheter 102 may notremove all of the clot material PE (or a desired amount of the clotmaterial PE) from the blood vessel BV. That is, a single aspiration maynot adequately remove the clot material PE from the blood vessel BV. Insuch instances, the user of the assembly 10 may wish to again applyvacuum pressure (conduct an “aspiration pass”) to remove all or aportion of the remaining clot material PE in the blood vessel BV. Insuch instances, the pressure source can be disconnected from the tubingsubsystem 120 and drained (e.g., aspirated clot removal removed) beforethe method 800 returns to block 802. For example, the adaptor 350 andthe syringe 340 can be decoupled from the connector 128, and the plunger342 can be pushed into the barrel 344 to expel the clot material PE andassociated fluid from the barrel 344 via the tip 347. With the distalportion of the catheter 102 positioned proximate to the remaining clotmaterial PE (e.g., unmoved relative the last aspiration pass), thepressure source can then be re-coupled to the connector 128 (block 804),primed again (block 806), and the vacuum pressure discharged (block 808)to aspirate all or a portion of the remaining clot material PE.

Blocks 802-808 can be repeated until a desired amount of clot materialis removed from the patient or until the catheter 102 becomes clogged.In some embodiments, to check for clogging of the catheter 102, thefluid control device 126 and/or the valve 106 can be opened to check forback bleeding. A lack of back bleeding can indicate that the catheter102 is likely clogged. Similarly, if the barrel 344 of the syringe 340contains mostly air and relatively little blood and clot material (e.g.,less than 5-10 cc) after aspiration of the catheter 102 (block 808), itcan indicate that the catheter 102 is likely clogged. When the catheter102 is clogged or a sufficient amount of clot material PE has beenremoved from the patient, the method 800 can proceed to block 810 andthe catheter 102 can be removed from the patient. When the catheter 102is clogged, the catheter 102 can be flushed and cleared prior to reentryinto the patient (block 802). In other embodiments, a different (e.g.,new, unused, etc.) catheter can be inserted into the patient andpositioned to remove the remaining clot material PE from the patient.

In some embodiments, rather than removing the catheter 102 from thepatient if the catheter 102 is clogged, the syringe 340 can be rechargedand used to apply one or more subsequent vacuum pulses to the catheter102. More specifically, the fluid control device 126 can be closed andthe syringe 340 can be removed from the connector 128 and evacuated toremove the clot material and blood therein. Then, blocks 804-808 can berepeated to apply another pulse of vacuum to the catheter 102. That is,rather than removing the catheter 102 after a clog is detected, thesyringe 340 can be “cycled” until the vacuum force on the clot materialPE overcomes the forces between the clot material PE and the catheter102 and sucks the clot material PE into the syringe 340. In someembodiments, when the pressure source 400 with the secondary syringe 460(FIGS. 4A-4C) is used with the primary syringe 340, the secondarysyringe 460 can be cycled one or more times to increase the vacuum inthe assembly 10 (e.g., in the catheter 102) and thus increase thesuction force exerted against the clot material PE. That is, rather thanremoving the catheter 102 after a clog is detected, the secondarysyringe 460 can be cycled until the vacuum force on the clot material PEovercomes the forces between the clot material PE and the catheter 102and sucks the clot material PE into the syringe 340. In someembodiments, as described in detail below with reference to FIGS.15-16E, a second clot removal assembly can be telescoped through thefirst assembly 10 to facilitate removal of the clogged clot material PE.

In some embodiments, an interventional device such as a clot removaland/or clot treatment device can be delivered to the treatment sitethrough the catheter 102 for engaging and facilitating clot removalbefore and/or after application of a stored vacuum to the catheter 102.Suitable interventional devices and associated methods are disclosed inU.S. Pat. No. 9,526,864, filed Jun. 9, 2015, and titled “RETRACTION ANDASPIRATION DEVICE FOR TREATING EMBOLISM AND ASSOCIATED SYSTEMS ANDMETHODS,” and U.S. Pat. No. 8,784,434, filed Mar. 15, 2013, and titled“METHODS AND APPARATUS FOR TREATING EMBOLISM,” both of which areincorporated herein by reference in their entireties. In someembodiments, for example, the user can first advance an interventionaldevice to the treatment site and at least partially engage the clotmaterial PE with the interventional device to loosen (e.g., scour) theclot material PE. Such loosening of the clot material PE can facilitatethe removal of the clot material PE upon a subsequent aspiration pass.Likewise, in some embodiments, the user can use an interventional deviceto engage residual clot material PE (FIG. 10B) after a first aspirationpass.

IV. Selected Embodiments of Telescoping Clot Removal Systems andAssociated Methods of Clot Removal

FIG. 11 is a partially schematic side view of another clot treatment orclot removal system configured in accordance with the presenttechnology. In the illustrated embodiment, the clot removal systemincludes a first aspiration assembly 20 and a second aspiration assembly30. The first and second aspiration assemblies 20, 30 (“assemblies 20,30”) can include some features generally similar to the features of theaspiration assembly 10 described in detail above with reference to FIGS.1-10B. For example, the first aspiration assembly 20 includes (i) afirst catheter subsystem 1000 having a first catheter 1002 and a firstvalve 1006, (ii) a first tubing subsystem 1020 having a first fluidcontrol device 1026 (e.g., a stopcock), and (iii) a first pressuresource 1040 that can be fluidly coupled to the first catheter subsystem1000 via the first tubing subsystem 1020. Likewise, the secondaspiration assembly 30 includes (i) a second catheter subsystem 1100having a second catheter 1102 and a second valve 1106, (ii) a secondtubing subsystem 1120 having a second fluid control device 1126 (e.g., astopcock), and (iii) a second pressure source 1140 that can be fluidlycoupled to the second catheter subsystem 1100 via the second tubingsubsystem 1120.

The first and second catheters 1002, 1102 each comprise an elongatedshaft defining a lumen 1004, 1104 and having a distal portion 1003 a,1103 a, respectively. The first and second valves 1006, 1106 eachinclude (i) a distal portion 1007 a, 1107 a, (ii) a proximal portion1007 b, 1107 b, (iii) a lumen 1009, 1109 extending therethrough, and(iv) a flow controller (obscured in FIG. 10 ) in the lumen 1009, 1109,respectively. The first fluid control device 1026 is operable toregulate or control fluid flow between (e.g., fluidly connect ordisconnect) the first pressure source 1040 and the first cathetersubsystem 1000. The second fluid control device 1126 is operable toregulate or control fluid flow between (e.g., fluidly connect ordisconnect) the second pressure source 1140 and the second cathetersubsystem 1100.

In the illustrated embodiment, the second catheter 1102 has a smallercross-sectional dimension (e.g., diameter) than the first catheter 1002so that the second catheter 1102 can be inserted through the first valve1006 and into the lumen 1004 of the first catheter 1002. In someembodiments, the second catheter 1102 can be telescoped through thelumen 1004 of the first catheter 1002 until the distal portion 1103 a ofthe second catheter 1102 extends beyond a distal terminus of the firstcatheter 1002. Accordingly, the second catheter 1102 can be longer thanthe first catheter 1002. In some embodiments, the second catheter 1102can have a size of 16 French or smaller and the first catheter 1002 canhave a size of 20 French or greater. The first valve 1006 can provide ahemostatic seal that inhibits fluid flow (e.g., blood flow) through thefirst valve 1006 and from the first catheter subsystem 1000 when thesecond catheter 1102 is positioned within the first catheter 1002. Insome embodiments (e.g., as described in detail below with reference toFIGS. 14A-14C), a sealing member 1499 can be positioned between thefirst catheter 1002 and the second catheter 1102 for sealing the lumen1004 of the first catheter 1002 when the second catheter 1102 isadvanced distally past the sealing member.

In some embodiments, the first and second pressure sources 1040, 1140(“pressure sources 1040, 1140”) are separate sources each configured togenerate and store a vacuum for subsequent application to the first andsecond catheter subsystems 1000, 1100, respectively, as described indetail above with reference to FIGS. 1-10B. In other embodiments, one orboth of the pressure sources 1040, 1140 can be configured to providesustained negative pressure rather than a charge or burst of storedvacuum pressure. In yet other embodiments, one of the pressures sources1040, 1140 can be omitted, or the pressure sources 1040, 1140 can befluidly coupled and/or integrally formed.

FIG. 12 is a flow diagram of a process or method 1280 for operating aclot removal system including the assemblies 20 and 30 to remove clotmaterial from within a blood vessel (e.g., a pulmonary blood vessel) ofa human patient in accordance with the present technology. FIGS. 13A-13Care schematic illustrations of a distal portion of the assemblies 20, 30during a clot removal procedure in accordance with the presenttechnology. FIGS. 14A-14C are schematic side views of a distal portionof the assemblies 20, 30 during a clot removal procedure and includingan optional sealing member in accordance with the present technology.Although some features of the method 1280 are described in the contextof the embodiments shown in FIGS. 11 and 13A-14C for the sake ofillustration, one skilled in the art will readily understand that themethod 1280 can be carried out using other suitable systems and/ordevices.

At block 1282, the method 1280 includes intravascularly positioning thefirst catheter 1002 within a human patient. FIG. 13A, for example,illustrates the first catheter 1002 after it has been advanced (e.g., asindicated by arrow A1) to a position within a blood vessel BV (e.g., apulmonary blood vessel). More specifically, the first catheter 1002 canbe advanced within the blood vessel BV until the distal portion 1003 aof the first catheter 1002 is positioned proximal to clot material PEwithin the blood vessel BV. In some embodiments, the position of thedistal portion 1003 a of the first catheter 1002 relative to the clotmaterial PE can be determined by activating the first valve 1006 anddetermining whether there is back-bleeding through the first valve 1006,as described in detail above. In the illustrated embodiment, the clotmaterial PE is located within a branch (e.g., a reduced diameterportion) of the blood vessel BV. In some embodiments, access to theblood vessel BV can be achieved using an introducer and guidewire asdescribed in detail above with reference to FIG. 8 .

At block 1284, the method 1280 includes advancing the second catheter1102 through the first catheter 1002 until the distal portion 1103 a ofthe second catheter 1102 is positioned proximate to the clot material PEwithin the blood vessel BV (e.g., at a treatment site). To advance thesecond catheter 1102 through the first catheter 1002, the user can firstinsert the distal portion 1103 a of the second catheter 1102 through thefirst valve 1006 before advancing the second catheter 1102 (e.g., asindicated by the arrow A1) through the lumen 1004 of the first catheter1002. In some embodiments, the first valve 1006 can be actuated (e.g.,by depressing one or more buttons) to open the lumen 1009 of the firstvalve 1006 so that the second catheter 1102 can be insertedtherethrough. In some embodiments, the position of the distal portion1103 a of the second catheter 1102 relative to the clot material PE canbe determined by activating the second valve 1106 and determiningwhether there is back-bleeding through the second valve 1106, asdescribed in detail above. In other embodiments, the (smaller) secondcatheter 1102 can be intravascularly positioned proximate to the clotmaterial PE before intravascularly positioning the (larger) firstcatheter 1002. In such embodiments, the second catheter 1102 can act asa guide or rail for guiding the advancement of the first catheter 1002to the treatment site.

FIG. 13A illustrates the second catheter 1102 after it has been advancedthrough the first catheter 1002 and past a distal terminus of the firstcatheter 1002 to position a distal terminus of the second catheter 1102proximate to a proximal portion of the clot material PE. In otherembodiments, the distal terminus of the second catheter 1102 can bepositioned at least partially within the clot material PE, or the distalterminus of the second catheter 1102 can be positioned distal of theclot material PE. In one aspect of the present technology, because thesecond catheter 1102 has a smaller cross-sectional dimension than thefirst catheter 1002, the second catheter 1102 can be advanced tonarrower (e.g., more distal) treatment sites within the blood vessel BV.In the embodiment illustrated in FIG. 13A, for example, the firstcatheter 1002 may be too large to be positioned within the branch of theblood vessel BV, while the second catheter 1102 can be positioned withinthe branch proximate to or within the clot material PE.

At block 1286, the method 1280 includes coupling the second pressuresource 1140 to the second catheter 1102 via the second fluid controldevice 1126. For example, any one or combination of the pressure sourcesdescribed in detail above with reference to FIGS. 2-7 can be coupled tothe second catheter 1102 via the second tubing subsystem 1120. Once thesecond pressure source 1140 is coupled to the second catheter 1102, (i)opening of the second fluid control device 1126 fluidly connects thesecond pressure source 1140 to the lumen 1104 of the second catheter1102, and (ii) closing of the second fluid control device 1126 fluidlydisconnects the second pressure source 1140 from the lumen 1104 of thesecond catheter 1102. In some embodiments, the method 1280 can furtherinclude coupling the first pressure source 1040 to the first catheter1002 (e.g., via the first tubing subsystem 1020).

At block 1288, the method 1280 includes activating the second pressuresource 1140 to generate a vacuum while the second fluid control device1126 is closed. In particular, the second pressure source 1140 can beactivated to build-up or pre-charge a vacuum for subsequent applicationto the second catheter 1102. In some embodiments, the first pressuresource 1040 can also be activated to generate and store a vacuum forsubsequent application to the first catheter 1002.

At block 1290, the method 1280 includes opening the second fluid controldevice 1126 to apply the vacuum stored in second pressure source 1140 tothe lumen 1104 of the second catheter 1102. As shown in FIG. 13B,application of the vacuum causes suction (e.g., as indicated by arrowA2) that aspirates at least a portion of the clot material PE from theblood vessel BV and into the lumen 1104 of the second catheter 1102. Insome embodiments, opening the second fluid control device 1126instantaneously or nearly instantaneously generates suction at thedistal portion 1103 a of the second catheter 1102. In one aspect of thepresent technology, pre-charging or storing the vacuum before applyingthe vacuum to the lumen 1104 of the second catheter 1102 is expected togenerate greater suction forces (and corresponding fluid flowvelocities) at and/or near the distal portion 1103 a of the secondcatheter 1102 compared to simply activating the second pressure source1140 while it is fluidly connected to the second catheter 1102.

In some embodiments, where the first pressure source 1040 is alsoactivated to generate and store a vacuum (e.g., at block 1288), themethod 1280 can further comprise opening the first fluid control device1026 to generate suction at the distal portion 1003 a of the firstcatheter 1002. One skilled in the art will understand that the suctionprofile in the blood vessel BV can be selected or modified based on thecharacteristics of the pressure sources 1040, 1140 (e.g., volume, boresize, etc.) and the timing of the opening of the first and second fluidcontrol devices 1026, 1126. For example, the first fluid control device1026 can be opened at the same time as the second fluid control device1126 to generate a combined and relatively large suction force in theblood vessel BV. In other embodiments, the first fluid control device1026 can be opened after the second fluid control device 1126 togenerate staggered or stepped suction forces in the blood vessel BV. Forexample, the first fluid control device 1026 can be opened after thesecond fluid control device 1126 to aspirate any of the clot material PE(i) remaining in the blood vessel BV after aspiration of the secondcatheter 1102 and/or (ii) stuck to or extending from the second catheter1102. In other embodiments, the first pressure source 1040 can be a pumpor other source for providing sustained negative pressure—rather than abuilt-up charge of negative pressure—and thus can generate sustained(e.g., constant) suction at the distal portion 1003 a of the firstcatheter 1002. In some such embodiments, the first fluid control device1026 can remain open during the clot removal procedure to providesustained suction throughout the procedure.

In some embodiments, an interventional device can be delivered throughthe second catheter 1102 and used to engage the clot material PE beforeand/or after the vacuum is applied to the second catheter 1102. Specificdetails of suitable interventional devices and associated methods of useare disclosed in, for example, provisional U.S. patent application Ser.No. 16/258,344, filed Jan. 25, 2019, and titled “SINGLE INSERTIONDELIVERY SYSTEM FOR TREATING EMBOLISM AND ASSOCIATED SYSTEMS ANDMETHODS,” which is incorporated herein by reference in its entirety.

At block 1292, the method 1280 includes retracting the second catheter1102 proximally through the first catheter 1002. In some embodiments,multiple aspiration passes can be performed with the second catheter1102 before retracting the second catheter 1102. In some embodiments, asshown in FIG. 13C, the first pressure source 1040 or another pressuresource coupled to the first catheter 1002 can be activated to generatesuction (e.g., as indicated by arrow A3) at the distal portion 1003 a ofthe first catheter 1002 during retraction of the second catheter 1102.The suction can be constant or provided in one or more bursts, asdescribed in detail above. In some embodiments, the second catheter 1102can be fully withdrawn from the patient and disposed of or cleaned(e.g., flushed with a sterile liquid) for reuse.

Sometimes, the clot material PE is not fully pulled into the secondcatheter 1102 when the vacuum is applied to the second catheter 1102(block 1290) and can therefore stick to or dangle from the distalportion 1103 a of the second catheter 1102. FIG. 14A, for example, is anenlarged view of the distal portion of the assemblies 20, 30 shown inFIG. 13C and illustrating a portion of the clot material PE stuck to ordangling from the distal portion 1103 a of the second catheter 1102. Inthe illustrated embodiment, an optional seal 1499 is disposed betweenthe first and second catheters 1002, 1102 to facilitate the removal ofsuch dangling clot material PE. More specifically, the seal 1499 (shownin cross-section) can be disposed between an outer surface of the secondcatheter 1102 and an inner surface of the first catheter 1002. The seal1499 can be an grommet, or other suitable component that fluidlydisconnects the lumen 1004 of the first catheter 1002 from the bloodvessel BV when the second catheter 1102 is positioned therethrough(e.g., when the distal terminus of the second catheter 1102 ispositioned distally of the seal 1499).

FIGS. 14B and 14C are enlarged views of the distal portion of theassemblies 20, 30 and illustrating further retraction of the secondcatheter 1102 (and the dangling clot material PE) into the lumen 1004 ofthe first catheter 1002. In some embodiments, the first pressure source1040 can be activated to charge a vacuum in the lumen 1004 of the firstcatheter 1002. For example, after the second catheter 1102 is advancedthrough the first catheter 1002 and past the seal 1499 (e.g., block1284)—thereby sealing the lumen 1004 of the first catheter 1002—theoperator can open the first fluid control device 1026 and activate thefirst pressure source 1040 to build up the vacuum in the lumen 1004 ofthe first catheter 1002. Referring to FIG. 14C, when the distal terminusof the second catheter 1102 is retracted proximally past the seal 1499,the lumen 1004 of the first catheter 1002 becomes fluidly connected tothe blood vessel BV and the vacuum is instantaneously or nearlyinstantaneously released to generate suction (e.g., as indicated byarrows A4). In the illustrated embodiment, the suction acts to separateor otherwise dislodge the clot material PE from the second catheter 1102and pull the clot material PE proximally through the lumen 1004 of thefirst catheter 1002. In this manner, a second burst of suction isautomatically applied via the first catheter 1002 during retraction ofthe second catheter 1102. In one aspect of the present technology, theuser does not need to take any additional step to release the vacuumstored in the first catheter 1002—as release is automatically triggeredby retraction of the second catheter 1102.

At block 1294, the user can determine whether it is necessary ordesirable to redeploy the second catheter 1102 or another catheterthrough the first catheter 1002 in order to remove any residual clotmaterial PE that was not removed during the first aspiration pass and/orany clot material located elsewhere in the blood vessel BV (e.g., toinitiate a second aspiration pass). In some embodiments, the operatorcan visualize the amount of clot material PE collected in the firstpressure source 1040 and/or the second pressure source 1140 to at leastpartially determine whether another aspiration pass is needed. In otherembodiments, the operator can rely on imaging (e.g., fluoroscopicimaging) of the blood vessel BV or other techniques known in the art todetermine whether an additional aspiration pass is necessary ordesirable.

If another pass is not needed (e.g., the clot material PE was adequatelyremoved), the user can elect to fully withdraw the assemblies 20, 30from the patient at block 1296. If clot material PE remains in thevessel, the method can return to block 1284. In particular, the samesecond catheter 1102 can be cleaned (e.g., flushed with saline) andadvanced again through the first catheter 1002 until the distal portion1103 a of the second catheter 1102 is positioned proximate to theremaining clot material PE within the blood vessel BV. In someembodiments, a new second catheter 1102 can be used for each pass toreduce the likelihood of contamination (e.g., reintroduction of clotmaterial PE). In some embodiments, the first catheter 1002 can beaspirated (e.g., via the first pressure source 1040) prior toredeployment of the second catheter 1102 to, for example, remove anyclot material PE that may be in the first catheter 1002 to inhibit itsreintroduction into the blood vessel BV as the second catheter 1102 isadvanced therethrough during another pass. Once the desired amount ofclot material PE has been removed from the patient, the assemblies 20,30 may be fully withdrawn from the patient (block 1294).

In one aspect of the present technology, the method 1280 provides for anaspiration catheter to be deployed multiple times without requiring thatthe first catheter 1002 be removed after each deployment. Accordingly,the present technology allows for only a single insertion of a guidecatheter during a procedure including multiple passes to remove clotmaterial—increasing the speed of the procedure and reducing trauma tothe patient since the guide catheter does not need to be reintroduced(e.g., advanced through the vasculature and past the heart) before eachpass. Moreover, in certain embodiments, the present technology canenable the first catheter 1002 to be relocated to an alternate treatmentsite within the patient without removing the first catheter 1002 fromthe patient and, therefore, without reintroducing the first catheter1002 through the heart. For example, the first catheter 1002 can berelocated to another treatment site within the lungs including atreatment site in the opposite lung. More specifically, (i) a dilatorcan be reintroduced into the first catheter 1002, (ii) the firstcatheter 1002 can be withdrawn into the main pulmonary artery, (iii) aguidewire can be redirected to the new treatment site, (iv) the firstcatheter 1002 can be advanced over the guidewire to the new treatmentsite, and (v) the dilator can be removed.

FIG. 15 is a flow diagram of another process or method 1580 foroperating a clot removal system including the assemblies 20, 30 (FIG. 1) to remove clot material from within a blood vessel (e.g., a pulmonaryblood vessel) of a human patient in accordance with the presenttechnology. FIG. 16A is an enlarged side view of a distal portion of thefirst assembly 20, and FIGS. 16B-16E are side views of a distal portionof the assemblies 20, 30 during a clot removal procedure in which clotmaterial clogs the first assembly 20 in accordance with the presenttechnology. Although some features of the method 1580 are described inthe context of the embodiments shown in FIGS. 11 and 16A-16E for thesake of illustration, one skilled in the art will readily understandthat the method 1580 can be carried out using other suitable systemsand/or devices.

Some features of the method 1580 are generally similar to those of themethods 880 and/or 1280 described in detail above with reference toFIGS. 8 and 12 , respectively. For example, at block 1582 the methodincludes intravascularly positioning the first catheter 1002 of thefirst assembly 20 within a human patient. At block 1584, the method 1580includes coupling the first pressure source 1040 to the first catheter1002 via the first fluid control device 1026. For example, any one orcombination of the pressure sources described in detail above withreference to FIGS. 2-7 can be coupled to the second catheter 1002 viathe first tubing subsystem 1020. At block 1586, the method 1580 includesactivating the first pressure source 1040 to generate a vacuum while thefirst fluid control device 1026 is closed. In particular, the firstpressure source 1040 can be activated to build-up or pre-charge a vacuumfor subsequent application to the first catheter 1002. At block 1588,the method 1580 includes opening the first fluid control device 1026 toapply the vacuum stored in the first pressure source 1040 to the lumen1004 of the first catheter 1002. As described in detail above, openingthe first fluid control device 1026 instantaneously or nearlyinstantaneously generates suction at the distal portion 1003 a of thefirst catheter 1002.

Sometimes, however, clot material is not fully pulled into the firstcatheter 1002 and/or clogs the first catheter 1002 when the vacuum isapplied to the first catheter 1002 (block 1588). FIG. 16A, for example,is an enlarged view of the distal portion of the first assembly 20illustrating a portion of clot material PE that extends beyond from thedistal portion 1003 a of the first catheter 1002 and blocks/clogs thelumen 1004 of the first catheter 1002. As such, a portion of the clotmaterial PE is not within the first catheter 1002. Accordingly, at block1590, the method 1580 can include determining whether the first catheter1002 is clogged. In some embodiments, the operator can determine thatthe first catheter 1002 is clogged based on the vacuum chamber of thefirst pressure source 1040 containing little to no clot material PE andblood. For example, since the clot material PE clogs the first catheter1002, the vacuum chamber of the first pressure source 1040 cavitateswhen the first fluid control device 1026 is opened. If the firstcatheter 1002 is not clogged, the method 1580 can proceed to block 1598and the first catheter 1002 can be withdrawn from the patient or theoperator can perform another aspiration pass (e.g., as described indetail above with reference to blocks 808 and 810 of the method 800shown in FIG. 8 ).

If the first catheter 1002 is clogged, the method 1580 can proceed toblock 1592 which includes advancing the second catheter 1102 through thefirst catheter 1002 until the distal portion 1103 a of the secondcatheter 1102 is positioned in or proximate to the clogging clotmaterial PE. For example, FIG. 16B illustrates the second catheter 1102after it has been advanced to a position within the first catheter 1002in which the distal terminus of the second catheter 1102 is at orproximate to the clogging clot material PE. To advance the secondcatheter 1102 through the first catheter 1002, the user can first insertthe distal portion 1103 a of the second catheter 1102 through the firstvalve 1006 (FIG. 11 ) before advancing the second catheter 1102 throughthe lumen 1004 of the first catheter 1002.

At block 1594, the method 1580 includes activating the second pressuresource 1140 (FIG. 11 ) coupled to the second catheter 1102. Morespecifically, the second pressure source 1140 (e.g., any one orcombination of the pressure sources described in detail above withreference to FIGS. 2-7 ) can be coupled to the second catheter 1102 viathe second fluid control device 1126 (FIG. 11 ), and the second pressuresource 1140 can be activated to build-up or pre-charge a vacuum whilethe second fluid control device 1126 is closed. The second fluid controldevice 1126 can then be actuated to apply the vacuum stored in thesecond pressure source 1140 to the lumen 1104 of the second catheter1102. In other embodiments, the second pressure source 1140 can simplyprovide a sustained vacuum rather than an instantaneous release ofvacuum. That is, in some embodiments the second pressure source 1140 isnot pre-charged with a vacuum.

Applying the vacuum to second catheter 1102 can aspirate at least aportion of the clogging clot material PE into the second catheter 1102and/or suck the clot material PE against the distal terminus of thesecond catheter 1102. FIG. 16C, for example, illustrates a portion ofthe clot material PE stuck to or extending from the distal portion 1103a of the second catheter 1102 after aspirating the second catheter 1102.In the embodiment illustrated in FIG. 16C, the added vacuum pressuregenerated through the second catheter 1102 is still not enough to breakapart the clot material PE such that it can be fully aspirated throughthe first and/or second catheters 1002, 1102. That is, the clot materialPE clogs the lumen 1004 of the first catheter 1002. In otherembodiments, the added vacuum pressure from the second pressure source1140 is sufficient to break apart the clot material PE such that it isaspirated into, for example, the vacuum chambers of the first and/orsecond pressure sources 1040, 1140.

At block 1596, the method can include retracting the second catheter1102 and the clot material PE through the lumen 1004 of the firstcatheter 1002. For example, FIG. 16D illustrates retracting the secondcatheter 1102, which in turn retracts the attached clot material PE,through the lumen 1004 of the first catheter 1002. In some embodiments,the second catheter 1102 and clot material PE can be fully withdrawnthrough the first catheter 1002. In other embodiments, retracting theclot material PE through the first catheter 1002 causes the clotmaterial PE to break apart and be aspirated into the vacuum chambers ofthe first and/or second pressure sources 1040, 1140. FIG. 16E, forexample, illustrates the clot material PE breaking apart as the vacuumof the first and/or second pressure sources 1040, 1140 isinstantaneously or nearly instantaneously released to suck the clotmaterial PE proximally (e.g., as indicated by arrows A5).

At block 1598, the first and second catheters 1002, 1102 can bewithdrawn from the patient or the operator can perform anotheraspiration pass using one or both of the first and second catheters1002, 1102.

In one aspect of the present technology, the method 1580 removes clotmaterial even when a first aspiration pass clogs the first catheter1002. More particularly, the second catheter 1102 can be used to removeclogged clot material PE without requiring the first catheter 1002 andthe clogged clot material PE to be withdrawn through the blood vesselBV.

V. Additional Selected Embodiments of Clot Removal Systems andAssociated Methods of Clot Removal

From the foregoing, it will be appreciated that specific embodiments ofthe present technology have been described herein for purposes ofillustration, but that various modifications may be made withoutdeviating from the scope of the present technology. For example, in manyof the embodiments described above, stored vacuum pressure can be usedto aspirate or suck clot material from a blood vessel and into acatheter without the need to engage an interventional device with theclot material. However, one skilled in the art will understand that theaspiration devices and techniques disclosed herein can be used inconjunction with any suitable interventional device and/or during a clotremoval procedure utilizing an interventional device. In someembodiments, for example, a clot removal system can be configured toapply stored vacuum pressure to a guide catheter to generate a burst ofsuction while an interventional device is retracted into and/or throughthe guide catheter.

FIG. 17 , for example, is a partially schematic view of a clot removalsystem 1700 (“system 1700”) configured in accordance with the presenttechnology. The system 1700 includes some features generally similar tothe features of the clot removal system described in detail above withreference to FIG. 1 . For example, the system 1700 includes a catheteror sheath 1702 comprising an elongated shaft, and a valve 1706 coupledto a proximal portion of the sheath 1702. The valve 1706 has a side port1708 that fluidly couples a lumen of the sheath 1702 to a tubingsubsystem 1720 and a pressure source 1740 (shown schematically). A fluidcontrol device 1726 (e.g., a stopcock or clamp; shown schematically) isoperable to fluidly disconnect or connect the pressure source 1740from/to the lumen of the sheath 1702. The pressure source 1740 can beany suitable pressure source for generating and storing vacuum pressure,as described in detail above.

In the illustrated embodiment, the system 1700 further includes (i) aself-expanding (e.g., mesh) funnel 1780 coupled to a proximal portion ofthe sheath 1702 and (ii) an interventional device (e.g., a thrombusextraction device) 1790. In the illustrated embodiment, theinterventional device 1790 includes an expandable coring element (e.g.,a first portion) 1792 coupled to an expandable cylindrical element(e.g., a second portion) 1794. In some embodiments, the interventionaldevice 1790 is configured to self-expand from a compressed deliverystate to an expanded deployed state. The interventional device 1790 isshown in the deployed state in FIG. 17 . An elongated shaft 1782 and/orone or more shafts positioned within the elongated shaft 1782 (e.g., anintermediate shaft 1884 and an inner shaft 1886 as shown in FIGS. 18Eand 18F, respectively) are coupled to the interventional device 1790 andconfigured to retract, advance, and/or manipulate (e.g., move betweenthe delivery and deployed states) the interventional device 1790. Insome embodiments, the system 1700 can be generally the same as orsimilar to any of the clot removal systems disclosed in U.S. PatentApplication Publication No. 2018/0193043, filed Apr. 26, 2017, andtitled “DEVICES AND METHODS FOR TREATING VASCULAR OCCLUSION,” which isincorporated herein by reference in its entirety.

In the illustrated embodiment, the system 1700 is shown intravascularlypositioned within a blood vessel BV of a human patient and proximate toclot material DV (e.g., a deep vein thrombus) within the blood vesselBV. Specifically, FIG. 17 shows the system 1700 after (i) advancing thesheath 1702 to a position proximate to a proximal portion 1785 b of theclot material DV, (ii) deploying the funnel 1780, (iii) deploying theinterventional device 1790 from the sheath 1702 (e.g., by advancing theinterventional device 1790 through the valve 1706 and the sheath 1702 toa position distal of a distal portion 1785 a of the clot material DV),and (iv) expanding the interventional device 1790 from the compresseddelivery state to the deployed state.

FIGS. 18A-18H are enlarged views of a distal portion of the system 1700during a clot removal procedure in accordance with the presenttechnology. In general, FIGS. 18A-18H illustrate the proximal retractionof the interventional device 1790 through the clot material DV tocapture at least a portion of the clot material DV, and the subsequentjoint retraction of the interventional device 1790 and the captured clotmaterial DV into the funnel 1780 and the sheath 1702. In one aspect ofthe present technology, charged vacuum pressure generated in the vacuumsource 1740 can be applied to the sheath 1702 at one or more timesduring the illustrated process to generate suction for aspirating thecaptured clot material DV through the sheath 1702 and/or to inhibitclogging of the sheath 1702.

Referring first to FIG. 18A, proximal retraction of the interventionaldevice 1790 causes the coring element 1792 to separate and/or core thedistal end portion 1785 a of the clot material DV from the walls W ofthe blood vessel BV. As shown in FIG. 18B, continued proximal retractionof the interventional device 1790 through the clot material DV causesthe cylindrical element 1794 to capture the distal end portion 1785 a ofthe clot material therein. FIGS. 18C-18E illustrate further proximalretraction of the interventional device 1790 which causes furtherseparation, coring, and/or capture of the clot material DV. As seen inFIG. 18E, the proximal end portion 1785 b of the clot material DV iscored and captured as the interventional device 1790 is proximallyretracted toward the funnel 1780 and the sheath 1702. As further shownin FIG. 18E, a first radiopaque marker 1887 a can be positioned on adistal end portion of the inner shaft 1884 and a second radiopaquemarker 1887 b can be positioned on a distal end portion of the sheath1702.

In some embodiments, as shown in FIG. 18F, the interventional device1790 can be proximally retracted until a portion of the coring element1792 is contained (e.g., positioned) within the funnel 1780. Morespecifically, the interventional device 1790 can be proximally retracteduntil a mouth 1895 of the coring element 1792 is contained within thefunnel 1780. In some embodiments, the containment of the mouth 1895within the funnel 1780 can be fluoroscopically verified by visualizationof the radiopaque markers 1887 (FIG. 18E). In some embodiments, forexample, the mouth 1895 can be determined as wholly contained within thefunnel 1780 via fluoroscopic monitoring based on the alignment of thedistal end portion of the inner shaft 1884 (e.g., the first radiopaquemarker 1885 a) relative to the distal end portion of the sheath 1702(e.g., the second radiopaque marker 1885 b). In some embodiments, whenthe mouth 1895 of the coring element 1792 is positioned within thefunnel 1780, the interventional device 1790 can be moved or transformedfrom the expanded deployed state to the compressed delivery state tocompress and secure the clot material DV captured by the interventionaldevice 1790. In some embodiments, for example, the intermediate shaft1884 can be unlocked and/or decoupled from the inner shaft 1886 (e.g.,via user actuation of a plunger or other device) such that the innershaft 1886 can be advanced distally relative to the intermediate shaft1884 to collapse or compress the interventional device 1790.

After the interventional device 1790 has been collapsed, theinterventional device 1790 can be proximally retracted through thefunnel 1780 and into the sheath 1702 as depicted in FIG. 18G. As shownin FIG. 18H, the interventional device 1790 can continue to beproximally retracted until the interventional device 1790 and thecaptured clot material DV are fully contained within the sheath 1702. Insome embodiments, the interventional device 1790 and the captured clotmaterial DV can then be withdrawn through the sheath 1702 and the valve1706 (FIG. 17 ), and from the patient's body.

In some embodiments, the collapse of the interventional device 1790and/or the retraction of the interventional device 1790 into the funnel1780 and/or the sheath 1702 can result in one or more portions of theclot material DV breaking away from the clot material DV contained inthe interventional device 1790. For example, all or a portion of thecaptured clot material DV can be extruded through pores of the (e.g.,mesh) cylindrical element 1794 as the interventional device 1790collapses. In some embodiments, any such clot material can be capturedby the funnel 1780. Referring to FIG. 17 , in some embodiments, thepressure source 1740 can be activated to charge a vacuum, and the fluidcontrol device 1726 can subsequently be opened to apply the chargedvacuum to the sheath 1702 (as described in detail above). The vacuum canbe applied to the sheath 1702 at any point during retraction of theinterventional device 1790. As shown in FIGS. 18G and 18H, applicationof the vacuum can generate instantaneous or nearly instantaneous suction(e.g., as indicated by arrows A6) at the distal end portion the sheath1702 that can aspirate the extruded portions and/or other portions ofthe clot material DV into and/or through the sheath 1702. In particular,the generated suction can aspirate some or all of the clot material DVcaptured by the funnel 1780. Moreover, in some embodiments, applicationof a vacuum from the pressure source 1740 can facilitate smoothretraction of the captured clot material DV through the sheath 1702. Forexample, a burst of suction generated by application of the vacuum canhelp inhibit clogging of the sheath 1702, and/or help resolve (e.g.,break apart) a clog formed in the sheath 1702 during retraction.

VI. Selected Embodiments of Clot Removal Systems Having Filters andAssociated Methods of Clot Removal

The systems and methods for clot removal described herein can includeapplying a pre-charged vacuum to generate suction for aspirating clotremoval from the blood vessel of a patient. In one aspect of the presenttechnology, aspiration of the clot material also aspirates blood fromthe patient. It can be advantageous to reintroduce the aspirated bloodto the patient to lessen the trauma to the patient—especially where theremoval procedure may comprise multiple aspiration passes that cantogether withdraw a significant amount of blood. However, the aspiratedblood is often mixed with clot material and is therefore not suitablefor reintroduction into the patient. FIGS. 19-20E illustrate variousdevices for filtering aspirated blood from removed clot material toreintroduce the aspirated blood into the patient without reintroducing asignificant amount of clot material.

For example, FIG. 19 is a perspective side view of a pressure source1900 for filtering blood from aspirated clot material during a clotremoval procedure configured in accordance with the present technology.The pressure source 1900 is generally similar to the pressure source 400described in detail above with reference to FIGS. 4A-4C. For example,the pressure source 1900 includes the secondary syringe 460 (“syringe460”) and the first and second one-way valves 470 and 472. However, thesecondary syringe 460 is coupled to a canister 1940 rather than theprimary syringe 340 (FIGS. 4A-4C). The canister 1940 includes a tip(obscured) coupled to the adaptor 350 and is configured to be removablypositioned within the connector 128 of the tubing subsystem 120 (FIG. 1) to fluidly couple the canister 1940 to the tubing subsystem 120.Because the canister 1940 does not include a plunger or other componentfor changing a volume thereof, the syringe 460 is the only vacuum sourcefor evacuating the canister 1940 (e.g., via repeated cycling of thesecondary syringe 460).

In the illustrated embodiment, the canister 1940 further includes afilter 1942. The canister 1940 is shown as transparent in FIG. 19 forthe sake of clarity. The filter 1942 is coupled to and/or covers aremovable end cap 1944 having a blood separation port 1946. Inoperation, when blood and clot material are aspirated into the canister1940 (e.g., via any of the methods described in detail above), thefilter 1942 separates the blood from the clot material within thecanister 1940. The filtered blood can be removed via the bloodseparation port 1946. For example, a syringe (not shown) or other devicecan be fluidly coupled to the blood separation port 1946 and used todraw the blood through the filter 1942 and out of the canister 1940. Thefiltered blood can then be reintroduced to the patient via, for example,the fluid control device 126 and/or the connector 128 of the tubingsubsystem 120. Once the blood is removed from the canister 1940, the endcap 1944 can be removed from the canister 1940 (e.g., by unscrewing theend cap 1944 from the body of the canister 1940) for removing thecaptured clot material. In some embodiments, the filter 1942 is attachedto the end cap 1944 such that removing the end cap 1944 removes thefilter 1942 and permits clot material to be dumped, scooped, orotherwise removed from the canister 1940.

FIGS. 20A-20E illustrate a filter device 2050 for filtering blood fromaspirated clot material during a clot removal procedure configured inaccordance with the present technology. The filter device 2050 isconfigured as an in-line filter for use with, for example, one or moreof the pressure sources described in detail above with reference toFIGS. 2-7 . For example, FIG. 20A is a partially-exploded side view ofthe filter device 2050 and the pressure source 340 (FIGS. 3A-3D). In theillustrated embodiment, the filter device 2050 comprises a filterportion 2060 that is removably positionable within a barrel portion2070. In the illustrated embodiment, the barrel portion 2070 includes abarrel 2072 that defines a chamber 2074, and a large bore tip 2076configured to fluidly couple the chamber 2074 to external components,such as the tubing subsystem 120 (e.g., as shown in FIG. 20C). Thefilter portion 2060 includes a seal 2062 configured to engage (i) aninterior surface of the barrel 2072 when the filter portion 2060 ispositioned within the chamber 2074 of the barrel portion 2070 and (ii)an exterior surface of the syringe 340 (e.g., an exterior surface of thebarrel 344) when the syringe 340 is inserted into the filter device2050. In other embodiments, the filter portion 2060 can be permanentlyattached to or integrally formed with the barrel portion 2070. Thefilter portion 2060 further includes a filter (e.g., a mesh) 2064configured (e.g., sized and shaped) to inhibit clot material frompassing therethrough. In some embodiments, the filter 2064 can beconfigured to inhibit clots larger than about 100 μm (e.g., larger thanabout 110 μm) from passing therethrough.

FIG. 20B is a perspective side view of the syringe 340 coupled to thefilter device 2050. The barrel 2072 of the barrel portion 2070 is shownas transparent in FIG. 20B (and FIGS. 20C-20E) for the sake of clarity.In the illustrated embodiment, the seal 2062 is positioned between theexterior surface of the barrel 344 of the syringe 340 and the interiorsurface of the barrel 2072 of the barrel portion 2070. The filter 2064is positioned around (e.g., covers) the tip 347 of the syringe 340 toinhibit clot material from entering the barrel 344 of the syringe 340during operation.

FIG. 20C is a side view of the filter device 2050 and syringe 340coupled to the tubing subsystem 120 of the assembly 10. Morespecifically, the tip 2076 can be inserted into the connector 128 of thetubing subsystem 120 as described in detail above. When the filterdevice 2050 and the syringe 340 are coupled to the tubing subsystem 120,the filter device 2050 is positioned in-line (e.g., in series) with thesyringe 340. In the embodiment illustrated in FIG. 20C, the plunger 342of the syringe 340 has been withdrawn to generate negative pressure inthe combined volume of the barrels 2072 and 344. As described in detailabove, opening the fluid control device 126 nearly instantaneouslyapplies the negative pressure to the catheter 102 to generate suctiontherein. When clot material and blood are aspirated through the catheter102 and the tubing subsystem 120, the filter portion 2060 inhibits theclot material from entering the barrel 344 of the syringe 340. Thus,aspirated blood is collected in the barrel 344 of the syringe 340 whilethe aspirated clot material is collected in the barrel 2072 of thebarrel portion 2070 of the filter device 2050. In this manner, clotmaterial and blood can be separated during aspiration.

In one aspect of the present technology, separating the blood from theclot material such that the blood is within the syringe 340 permits theblood to be easily reintroduced to the patient. For example, FIGS. 20Dand 20E are side views of the syringe 340 coupled to the tubingsubsystem 120 of the assembly 10 for reintroducing blood to a patient.In some embodiments, as shown in FIG. 20D, the syringe 340 can bedecoupled from the filter device 2050 and directly coupled to theconnector 128. With the fluid control device 126 in an open position,the blood can then be reintroduced to the patient through the assembly10 by depressing the plunger 342 of the syringe 340. In someembodiments, as shown in FIG. 20E, the syringe 340 can be decoupled fromthe filter device 2050 and directly coupled to a port on the fluidcontrol device 126. With the fluid control device 126 in a closedposition, the blood can then be reintroduced to the patient through theassembly 10 by depressing the plunger 342 of the syringe 340. Referringto FIGS. 20A-20E together, after or before reintroducing filtered bloodto the patient, the filter portion 2060 of the filter device 2050 can beremoved from the barrel portion 2070 so that the collected clot materialcan be removed and the filter device 2050 cleaned. In some embodiments,the filter device 2050 and a coupled pressure source can be used tofilter blood from clot material after—as opposed to during—an aspirationpass. For example, the filter device 2050 and coupled pressure sourcecould be used to withdraw blood and clot material collected in thecanister 1940 of the pressure source 1900 (e.g., where the canister 1940does not include the filter 1942).

FIGS. 21A and 21B illustrate a filter device 2150 for filtering bloodfrom aspirated clot material during a clot removal procedure configuredin accordance with the present technology. The filter device 2150 isconfigured for use with, for example, one or more of the pressuresources described in detail above with reference to FIGS. 2-7 . Forexample, FIG. 21A is a partially-exploded side view of the filter device2150 and the pressure source 340 (FIGS. 3A-3D). In the illustratedembodiment, the filter device 2150 includes a housing 2152 defining achamber 2154, a filter 2156 configured to be positioned within thehousing 2152, and a cap assembly 2160 configured to be releasablycoupled to the housing 2152 (e.g., via a threaded connection, snap-fitconnection, etc.). In some embodiments, the filter 2156 can have aporosity of between about 50-200 microns.

The housing 2152 can include a port 2153 configured to be removably,fluidly coupled to the pressure source 340 via a tubing subsystem 2120.In the illustrated embodiment, the tubing subsystem 2120 includes tubingsections 2124 (individually labeled as a first tubing section 2124 a anda second tubing section 2124 b), a fluid control device 2126 (e.g., avalve, stop cock, clamp, etc.), and a connector 2128 (e.g., a large boreconnector) for fluidly coupling the tubing subsystem 2120 to thepressure source 340. In the illustrated embodiment, the cap assembly2160 includes a fluid connector 2162 (e.g., a standard Luer or largebore connector) configured to be connected to a receiving/reinfusionsyringe 2170 via, for example, a tubing section 2164. In someembodiments, the cap assembly 2160 can include a valve (e.g., a one-wayvalve, a check valve, etc.) that provides for one-way fluid flow throughfilter assembly 2150.

In operation, during a clot removal procedure, the pressure source 340can be decoupled from the connector 128 (FIG. 1 ) after an aspirationpass and when the pressure source 340 is full of blood and clotmaterial. After connecting the filter device 2150 to the receivingsyringe 2170, the pressure source 340 can be coupled to the filterdevice 2150. For example, FIG. 21B is a perspective side view of thefilter device 2150 coupled to (i) the pressure source 340 via the tubingsubsystem 2120 and (ii) the reinfusion syringe 2170 via the tubingsection 2164. More specifically, referring to FIGS. 21A and 21Btogether, the tip 347 of the pressure source 340 can be coupled to theconnector 2128 of the tubing subsystem 2120, and a tip 2172 of thereinfusion syringe 2170 can be coupled to the tubing section 2164. Inother embodiments, the filter device 2150 can be coupled to the pressuresource 340 and/or the reinfusion syringe 2170 in other manners (e.g.,directly such that the all or part of the tubing subsystem 120 isomitted). Alternatively, the filter device 2150 can be directly attachedto the side port 108 (FIG. 1 ), an IV line (not shown), or anothersuitable connection point for reintroducing blood to the patient,

After coupling the pressure source 340 to the filter device 2150, thefluid control device 2128 can be opened to fluidly connect the pressuresource 340 to the filter device 2150. Then, the operator can depress theplunger 342 of the pressure source 340 to drive the blood and clotmaterial from the pressure source 340 into and/or through the filterdevice 2150. The filter 2156 of the filter device 2150 filters the bloodfrom the clot material such that the blood flows into the reinfusionsyringe 2170 and the clot material remains in the chamber 2154 of thefilter device 2150. For example, as shown in FIG. 21B, blood B fills thereinfusion syringe 2170 and clot material PE remains within the chamber2154 of the filter device 2150 after depressing the plunger 342 of thepressure source 340 in the direction indicated by the arrow H.

Next, the reinfusion syringe 2170 can be decoupled from the filterdevice 2150 so that the blood B can be reintroduced to the patient. Forexample, the reinfusion syringe 2170 could be directly coupled to a porton the fluid control device 126 (FIG. 1 ). The cap assembly 2160 can bedecoupled from the housing 2152 of the filter device 2150 to, forexample, permit an operator to remove the clot material PE collected inthe housing 2152 and thereby clean and prepare the filter device 2150for another use.

FIG. 22 is a partially-exploded side view of a filter device 2250 forfiltering blood from aspirated clot material during a clot removalprocedure configured in accordance with the present technology. Thefilter device 2250 is configured for use with, for example, one or moreof the pressure sources described in detail above with reference toFIGS. 2-7 . In general, the filter device 2250 is generally similar tothe filter device 2150 described in detail with reference to FIGS. 21Aand 21B. For example, the filter device 2250 includes a housing 2252defining a chamber 2254, a filter 2256 configured to be positionedwithin the housing 2252, and a cap assembly 2260 configured to bereleasably coupled to the housing 2252. However, in the illustratedembodiment the filter device 2250 includes a port 2253 that is directlyconnected to a connector 2228 configured to be coupled to a pressuresource (e.g., the pressure source 340 shown in FIGS. 3A-3D). The capassembly 2260 includes a fluid connector 2162 (e.g., a standard Luer orlarge bore connector) configured to be connected to a reinfusionsyringe, a sheath, an IV line, etc., (not shown). In some embodiments,the fluid connector 2262 is angled relative to the filter 2260 and/orthe housing 2252. For example, the fluid connector 2262 is formed tohave an approximately right angle in FIG. 22 . In one aspect of thepresent technology, this arrangement makes the filter device moreergonomic during use.

FIG. 23 is a partially-exploded side view of a filter device 2350 forfiltering blood from aspirated clot material during a clot removalprocedure configured in accordance with the present technology. Thefilter device 2350 is configured for use with, for example, one or moreof the pressure sources described in detail above with reference toFIGS. 2-7 . The filter device 2350 is generally identical to the filterdevice 2250 described in detail with reference to FIG. 22 —including,for example, the housing 2252 (“a first housing 2252”), the filter 2256(“a first filter 2256”), and the cap assembly 2260 including the fluidconnector 2262 (“a first fluid connector 2262”). However, in theillustrated embodiment a second housing 2382 and a second filter 2386are fluidly connected to the fluid connector 2262. The second housing2382 includes a second fluid connector 2384 that can be fluidlyconnected to a reinfusion syringe, a sheath, an IV line, etc., (notshown). The second filter 2386 is configured to provide a second stageof filtration. For example, in some embodiments the first filter 2256has a larger porosity than the second filter 2386. For example, thefirst filter 2256 can have a porosity of between about 50-200 micronsand the second filter 2386 can have a porosity of between about 50-170microns.

In general, one skilled in the art will understand that the variousembodiments of filter devices disclosed herein may have differentcomponents or combinations of components. For example, the filterdevices 2050, 2150, 2250, and/or 2350 (“the filter devices”) could beutilized with any of several different pressure sources other than thesyringe 340 (e.g., those shown in FIGS. 2 and 4-7 ). In someembodiments, the filter devices can be formed as a component of thetubing subsystem 120 (FIG. 1 ). Moreover, the filter devices can includeany number of filters and/or housings to provide any number offiltration stages.

CONCLUSION

The above detailed descriptions of embodiments of the technology are notintended to be exhaustive or to limit the technology to the precise formdisclosed above. Although specific embodiments of, and examples for, thetechnology are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the technologyas those skilled in the relevant art will recognize. For example,although steps are presented in a given order, alternative embodimentsmay perform steps in a different order. The various embodimentsdescribed herein may also be combined to provide further embodiments.

From the foregoing, it will be appreciated that specific embodiments ofthe technology have been described herein for purposes of illustration,but well-known structures and functions have not been shown or describedin detail to avoid unnecessarily obscuring the description of theembodiments of the technology. Where the context permits, singular orplural terms may also include the plural or singular term, respectively.

Moreover, unless the word “or” is expressly limited to mean only asingle item exclusive from the other items in reference to a list of twoor more items, then the use of “or” in such a list is to be interpretedas including (a) any single item in the list, (b) all of the items inthe list, or (c) any combination of the items in the list. Additionally,the term “comprising” is used throughout to mean including at least therecited feature(s) such that any greater number of the same featureand/or additional types of other features are not precluded. It willalso be appreciated that specific embodiments have been described hereinfor purposes of illustration, but that various modifications may be madewithout deviating from the technology. Further, while advantagesassociated with some embodiments of the technology have been describedin the context of those embodiments, other embodiments may also exhibitsuch advantages, and not all embodiments need necessarily exhibit suchadvantages to fall within the scope of the technology. Accordingly, thedisclosure and associated technology can encompass other embodiments notexpressly shown or described herein.

We claim:
 1. A method for the intravascular treatment of clot materialfrom within a blood vessel of a human patient, the method comprising:positioning a first catheter within a second catheter such that a distalportion of the first catheter is at a treatment site proximate to theclot material within the blood vessel; coupling a first pressure sourceto the first catheter via a fluid control device, wherein (a) opening ofthe fluid control device fluidly connects the first pressure source tothe first catheter and (b) closing of the fluid control device fluidlydisconnects the first pressure source from the first catheter;activating the first pressure source to generate a vacuum while thefluid control device is closed; opening the fluid control device toapply the vacuum to the first catheter to thereby aspirate at least aportion of the clot material into the first catheter; coupling a secondpressure source to the second catheter; and activating the secondpressure source to generate suction at the distal portion of the secondcatheter.
 2. The method of claim 1 wherein positioning the firstcatheter within the second catheter includes advancing the firstcatheter through the second catheter after positioning the secondcatheter within the blood vessel.
 3. The method of claim 1 whereinpositioning the first catheter within the second catheter includesadvancing the second catheter over the first catheter after positioningthe first catheter within the blood vessel.
 4. The method of claim 1wherein the first catheter has a size of 16 French, and wherein thesecond catheter has a size of 24 French.
 5. The method of claim 1wherein the first catheter has a first length, and wherein the secondcatheter has a second length shorter than the first length.
 6. Themethod of claim 1 wherein the first pressure source is the same as thesecond pressure source.
 7. The method of claim 1 wherein the firstpressure source and the second pressure source comprise an electricpump.
 8. The method of claim 1 wherein activating the second pressuresource includes activating the second pressure source after opening thefluid control device to apply the vacuum to the first catheter.
 9. Themethod of claim 1 wherein activating the second pressure source includesactivating the second pressure source before opening the fluid controldevice to apply the vacuum to the first catheter.
 10. The method ofclaim 1 wherein positioning the first catheter within the secondcatheter includes inserting the first catheter through a hemostasisvalve coupled to a proximal portion of the second catheter.
 11. Themethod of claim 10 wherein the method further comprises depressing abutton of the hemostasis valve to unseal a lumen of the hemostasis valvewhile inserting the first catheter through the hemostasis valve.
 12. Themethod of claim 1 wherein positioning the first catheter within thesecond catheter includes positioning the distal portion of the firstcatheter distal of a distal end portion of the second catheter.
 13. Themethod of claim 1 wherein the first pressure source is a first syringe,and wherein the second pressure source is a second syringe.
 14. Themethod of claim 1 wherein the clot material comprises a pulmonaryembolism.
 15. The method of claim 1 wherein the clot material comprisesa deep vein thrombus.
 16. The method of claim 1 wherein— the fluidcontrol device is a first fluid control device, coupling the secondpressure source to the second catheter includes coupling the secondpressure source to the second catheter via a second fluid controldevice, opening of the second fluid control device fluidly connects thesecond pressure source to the second catheter, and closing of the secondfluid control device fluidly disconnects the second pressure source fromthe second catheter.
 17. The method of claim 16 wherein activating thesecond pressure source to generate suction at the distal portion of thesecond catheter comprises: activating the second pressure source togenerate a vacuum while the second fluid control device is closed; andopening the second fluid control device to apply the vacuum to thesecond catheter to thereby generate the suction at the distal portion ofthe second catheter.
 18. A method for the intravascular treatment ofclot material from within a blood vessel of a human patient, the methodcomprising: positioning a first catheter within a second catheter withinthe blood vessel; coupling a first pressure source to the first cathetervia a first fluid control device, wherein (a) opening of the first fluidcontrol device fluidly connects the first pressure source to the firstcatheter and (b) closing of the first fluid control device fluidlydisconnects the first pressure source from the first catheter; couplinga second pressure source to the second catheter via a second fluidcontrol device, wherein (a) opening of the second fluid control devicefluidly connects the second pressure source to the second catheter and(b) closing of the second fluid control device fluidly disconnects thesecond pressure source from the second catheter; activating the firstpressure source to generate a first vacuum while the first fluid controldevice is closed; activating the second pressure source to generate asecond vacuum while the second fluid control device is closed; openingthe first fluid control device to apply the first vacuum to the firstcatheter to thereby aspirate at least a first portion of the clotmaterial into the first catheter; and opening the second fluid controldevice to apply the second vacuum to the second catheter to therebyaspirate at least a second portion of the clot material into the secondcatheter.
 19. The method of claim 18 wherein positioning the firstcatheter within the second catheter includes advancing the firstcatheter through the second catheter after positioning the secondcatheter within the blood vessel, and wherein opening the first fluidcontrol device includes opening the first fluid control device to applythe first vacuum to the first catheter after opening the second fluidcontrol device to apply the second vacuum to the second catheter. 20.The method of claim 18 wherein the first pressure source and the secondpressure source comprise an electric pump, and wherein positioning thefirst catheter within the second catheter includes inserting the firstcatheter through a hemostasis valve coupled to a proximal portion of thesecond catheter.
 21. The method of claim 1 wherein positioning the firstcatheter within the second catheter includes positioning the distalportion of the first catheter distal of a distal end portion of thesecond catheter.